Remove cdt-gdb-vscode from auto-publish

[jreineckearm]

We have started updating CI in https://github.com/eclipse-cdt-cloud/cdt-gdb-vscode to allow a manual release process.
We'd like to remove this extension from the auto-publishing scripts to avoid conflicts going forward.

See:

publish-extensions/extensions.json

Line 284 in 86a1fec

"eclipse-cdt.cdt-gdb-vscode": {

CC: @jonahgraham , @thegecko , @spoenemann

Happy to open a PR.

[filiptronicek]

Hey @jreineckearm, amazing to hear publishing has been set up on your side. Opening a PR would be much appreciated, it should be just the one line in the extensions.json file.