Python: added operationid validation in openapi spec

[sshandilya1991]

Description
This PR enforces the presence of an explicit operationId for every operation in the OpenAPI specification. Previously, if operationId was missing, a default value was generated using the path and HTTP method. Now, the parser will raise a PluginInitializationError if operationId is not provided, ensuring that all operations are uniquely and explicitly identified as required by the OpenAPI standard.

Key changes:

• Added validation to check for the existence of operationId in each operation.
• If operationId is missing, a clear error is raised, preventing fallback to a default value.
• python/tests/unit/connectors/openapi_plugin/no-operationid-openapi.yaml serves as a test case.
• Closes Bug: OpenAPI plugin function name parsing results in invalid kernel function name #12443

Edit:

• Added more validation for operationId to be unique & throw in case duplicate operationId found while parsing.

[sshandilya1991]

trying to address - #12443

[sshandilya1991]

@microsoft-github-policy-service agree company="Microsoft"

[markwallace-microsoft]

Python Test Coverage Report •

File	Stmts	Miss	Cover	Missing
connectors/openapi_plugin
openapi_parser.py	127	9	92%	61, 118, 182, 236, 239, 253–254, 257–258
TOTAL	26437	4520	82%

Python Unit Test Overview

Tests	Skipped	Failures	Errors	Time
3638	22 💤	0 ❌	0 🔥	1m 54s ⏱️

[moonbox3]

Thank you for the contribution.