fix: Runtime issue of ShellRepository.findByIdExternalAndExternalSubjectId()

[sm29105]

Issue:
With a growing number of shells registered ShellRepository.findByIdExternalAndExternalSubjectId() has an exponentially growing run time when accessed by a different one than the owning tenant id.

Solution:
The fix replaces the expensive IN statement in the WHERE clause of the backing SQL command by a much more cheaper EXISTS statement.

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• DEPENDENCIES are up-to-date. Dash license tool. Committers can open IP issues for restricted libs.
• Copyright and license header are present on all affected files

[sonarqubecloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

No Coverage information
No Duplication information

[gerbigf]

@thomas-henn, FYI. The issue of exponential runtime really blocked and blocks us in our go-live preparations. Please review the PR and provide feedback to us!

[sm29105]

Note. After a hint from @gerbigf I now also signed the ECA from the Eclipse Foundation.

[tunacicek]

LGTM