add IDENTITY_TYPE_MANUAL support

[gertd]

This PR adds support for IDENTITY_TYPE_MANUAL

When using an IdentityContext.Type == IDENTITY_TYPE_MANUAL, the identity field of the identity context will be passed as-is, and will surface in the input.identity.identity field. The resulting input.user object, which normally contains the properties of the resolve user object, will now be empty.

Example query using a manual identity context:

{
  "query": "i = input",
  "identityContext": {
    "identity": "[email protected]",
    "type": "IDENTITY_TYPE_MANUAL"
  }
}

Resulting input object:

{
  "response": {
    "result": [
      {
        "bindings": {
          "i": {
            "identity": {
              "identity": "[email protected]",
              "type": "IDENTITY_TYPE_MANUAL"
            },
            "user": {}
          }
        }
      }
    ]
  },
  "metrics": {},
  "trace": [],
  "trace_summary": []
}

[github-actions]

Pull Request Test Coverage Report for Build 6331020029

• 0 of 5 (0.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.04%) to 29.565%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
pkg/app/impl/jwt.go	0	5	0.0%

Totals
Change from base Build 6321753654:	-0.04%
Covered Lines:	1127
Relevant Lines:	3812

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💛 - Coveralls