[HTTP_endpoint] New input package

[P1llus]

What does this PR do?

This adds a custom input package for the http_endpoint input.

Checklist

• I have reviewed tips for building integrations and this pull request is aligned with them.
• I have verified that all data streams collect metrics or logs.
• I have added an entry to my package's changelog.yml file.
• I have verified that Kibana version constraints are current according to guidelines.

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Pinging @elastic/security-external-integrations (Team:Security-External Integrations)

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• Start Time: 2022-02-21T20:49:45.074+0000

• Duration: 21 min 29 sec

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Test	Results
Failed	0
Passed	3
Skipped	0
Total	3

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Package filestream - 1.0.0 containing this change is available at https://epr.elastic.co/search?package=filestream