[grid] Retry session only when capabilities are found. Add test to confirm session retry due to unexpected error.

[pujagani]

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Description

The distributor should not retry session if capabilities do not exist in any of the nodes.
Add a test to verify that session retry occurs if an unexpected error is thrown during session creation.

Motivation and Context

The changes avoid unnecessary retry of new session requests due to no matching capabilities in any of the nodes.
However, the test case confirms the session is retried if capabilities exist but an expected error is thrown during session creation.

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.