DDF-6714 add plugin support to websockets (#6715)

[glenhein]

What does this PR do?

Forward port of https://github.com/codice/ddf/pull/6715

Add plugin support to websockets so downstream projects inject special processing logic for web socket connections.

Who is reviewing it?

@clockard @derekwilhelm

Select relevant component teams:

Ask 2 committers to review/merge the PR and tag them here.

@jlcsmith

How should this be tested?

Any background context you want to provide?

What are the relevant tickets?

Fixes: https://github.com/codice/ddf/issues/6714

Screenshots

Checklist:

• [ ] Documentation Updated
• [ ] Update / Add Threat Dragon models
• [ ] Update / Add Unit Tests
• [ ] Update / Add Integration Tests

Notes on Review Process

Please see Notes on Review Process for further guidance on requirements for merging and abbreviated reviews.

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[jlcsmith]

build now

[cxddfbot]

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[cxddfbot]

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