Java: Add models for spring WebSocketHandler

[joefarebrother]

Adds remote flow sources for parameters of WebSocketHandler methods, and taint steps for related types.

[github-actions[bot]]

:warning: The head of this PR and the base branch were compared for differences in the framework coverage reports. The generated reports are available in the artifacts of this workflow run. The differences will be picked up by the nightly job after the PR gets merged.

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java

Generated file changes for java

• Changes to framework-coverage-java.rst:

-    `Spring <https://spring.io/>`_,``org.springframework.*``,38,486,143,26,,28,14,,35
+    `Spring <https://spring.io/>`_,``org.springframework.*``,47,492,143,26,,28,14,,35
-    Totals,,330,26361,2656,404,16,128,33,1,409
+    Totals,,339,26367,2656,404,16,128,33,1,409

• Changes to framework-coverage-java.csv:

+ org.springframework.web.socket,,9,6,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,9,6,