[Bug] Spec documentation doesn't build with Hugo 0.141+

[TheArcaneBrony]

Possibly related to the template that's used:

matrix-spec-cb83c5a-go-modules> Running phase: buildPhase
matrix-spec-cb83c5a-go-modules> hugo: downloading modules …
matrix-spec-cb83c5a-go-modules> hugo: collected modules in 37792 msStart building sites …
matrix-spec-cb83c5a-go-modules> hugo v0.143.1+extended+withdeploy linux/amd64 BuildDate=unknown VendorInfo=nixpkgs
matrix-spec-cb83c5a-go-modules> ERROR render of "/build/source/content/changelog/v1.12.md" failed: "/build/source/layouts/docs/baseof.html:14:7": execute of template failed: template: docs/changelog.html:14:7: executing "docs/changelog.html" at <partial "head.html" .>: error calling partial: "/build/hugo_cache/modules/filecache/modules/pkg/mod/github.com/matrix-org/[email protected]/layouts/partials/head.html:29:10": execute of template failed: template: partials/head.html:29:10: executing "partials/head.html" at <partial "dl-asset.html" "https://code.jquery.com/jquery-3.7.1.min.js">: error calling partial: "/build/hugo_cache/modules/filecache/modules/pkg/mod/github.com/matrix-org/[email protected]/layouts/partials/dl-asset.html:12:10": execute of template failed: template: partials/dl-asset.html:12:10: executing "partials/dl-asset.html" at <.Err>: can't evaluate field Err in type resource.Resource
matrix-spec-cb83c5a-go-modules> ERROR render of "/build/source/content/_index.md" failed: "/build/source/layouts/docs/baseof.html:14:7": execute of template failed: template: docs/list.html:14:7: executing "docs/list.html" at <partial "head.html" .>: error calling partial: "/build/hugo_cache/modules/filecache/modules/pkg/mod/github.com/matrix-org/[email protected]/layouts/partials/head.html:29:10": execute of template failed: template: partials/head.html:29:10: executing "partials/head.html" at <partial "dl-asset.html" "https://code.jquery.com/jquery-3.7.1.min.js">: error calling partial: "/build/hugo_cache/modules/filecache/modules/pkg/mod/github.com/matrix-org/[email protected]/layouts/partials/dl-asset.html:12:10": execute of template failed: template: partials/dl-asset.html:12:10: executing "partials/dl-asset.html" at <.Err>: can't evaluate field Err in type resource.Resource
matrix-spec-cb83c5a-go-modules> ERROR render of "/build/source/content/appendices.md" failed: "/build/source/layouts/docs/baseof.html:14:7": execute of template failed: template: docs/single.html:14:7: executing "docs/single.html" at <partial "head.html" .>: error calling partial: "/build/hugo_cache/modules/filecache/modules/pkg/mod/github.com/matrix-org/[email protected]/layouts/partials/head.html:29:10": execute of template failed: template: partials/head.html:29:10: executing "partials/head.html" at <partial "dl-asset.html" "https://code.jquery.com/jquery-3.7.1.min.js">: error calling partial: "/build/hugo_cache/modules/filecache/modules/pkg/mod/github.com/matrix-org/[email protected]/layouts/partials/dl-asset.html:12:10": execute of template failed: template: partials/dl-asset.html:12:10: executing "partials/dl-asset.html" at <.Err>: can't evaluate field Err in type resource.Resource
matrix-spec-cb83c5a-go-modules> ERROR render of "/build/source/content/changelog/v1.2.md" failed: "/build/source/layouts/docs/baseof.html:14:7": execute of template failed: template: docs/changelog.html:14:7: executing "docs/changelog.html" at <partial "head.html" .>: error calling partial: "/build/hugo_cache/modules/filecache/modules/pkg/mod/github.com/matrix-org/[email protected]/layouts/partials/head.html:29:10": execute of template failed: template: partials/head.html:29:10: executing "partials/head.html" at <partial "dl-asset.html" "https://code.jquery.com/jquery-3.7.1.min.js">: error calling partial: "/build/hugo_cache/modules/filecache/modules/pkg/mod/github.com/matrix-org/[email protected]/layouts/partials/dl-asset.html:12:10": execute of template failed: template: partials/dl-asset.html:12:10: executing "partials/dl-asset.html" at <.Err>: can't evaluate field Err in type resource.Resource
matrix-spec-cb83c5a-go-modules> Total in 42998 ms
matrix-spec-cb83c5a-go-modules> Error: error building site: render: failed to render pages: render of "/404" failed: "/build/hugo_cache/modules/filecache/modules/pkg/mod/github.com/matrix-org/[email protected]/layouts/_default/baseof.html:7:7": execute of template failed: template: 404.html:7:7: executing "404.html" at <partial "head.html" .>: error calling partial: "/build/hugo_cache/modules/filecache/modules/pkg/mod/github.com/matrix-org/[email protected]/layouts/partials/head.html:29:10": execute of template failed: template: partials/head.html:29:10: executing "partials/head.html" at <partial "dl-asset.html" "https://code.jquery.com/jquery-3.7.1.min.js">: error calling partial: "/build/hugo_cache/modules/filecache/modules/pkg/mod/github.com/matrix-org/[email protected]/layouts/partials/dl-asset.html:12:10": execute of template failed: template: partials/dl-asset.html:12:10: executing "partials/dl-asset.html" at <.Err>: can't evaluate field Err in type resource.Resource: Resource.Err was removed in Hugo v0.141.0 and replaced with a new try keyword, see https://gohugo.io/functions/go-template/try/