[grid] Make event bus listener for Queuer and LocalQueue thread-safe

[pujagani]

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Description

Adding Rentrant lock to ensure thread-safety.

Motivation and Context

Running concurrent tests on the Grid leads to some sessions getting created but hanging indefinitely. This could be potentially due to a race-condition while sending the response back to the client.
Running concurrently tests on Grid also leads to an error while sending to event bus from the LocalNewSessionQueue, this also could be potentially due to firing the event after releasing the lock. The changes attempt to fix these issues.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• I have read the contributing document.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.

[sonarqubecloud]

SonarCloud Quality Gate failed.

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

0.0% Coverage
0.0% Duplication

[diemol]

Thank you, @pujagani!