Fix: Vertex Fails to parse some function parameters

[davidmotson]

String parameters previously failed to parse raw due to ambiguity of the JsonFormat. The key is to not parse them as JsonElements and then convert them to strings.

That fix is here along with regression tests.

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Release note changes

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CHANGELOG.md file(s).

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Unit Test Results

  16 files   -   32    16 suites   - 32   15s ⏱️ - 1m 8s
108 tests  - 376  108 ✔️  - 376  0 💤 ±0  0 ❌ ±0 
216 runs   - 752  216 ✔️  - 752  0 💤 ±0  0 ❌ ±0 

Results for commit b7af14d. ± Comparison against base commit bb5a4d4.

This pull request removes 484 and adds 108 tests. Note that renamed tests count towards both.

com.google.firebase.dataconnect.AnyValueSerializerUnitTest ‑ descriptor should have expected values
com.google.firebase.dataconnect.AnyValueSerializerUnitTest ‑ deserialize() should throw UnsupportedOperationException
com.google.firebase.dataconnect.AnyValueSerializerUnitTest ‑ serialize() should throw UnsupportedOperationException
com.google.firebase.dataconnect.AnyValueUnitTest ‑ constructor(Boolean) creates an object with the expected value
com.google.firebase.dataconnect.AnyValueUnitTest ‑ constructor(Double) creates an object with the expected value (edge cases)
com.google.firebase.dataconnect.AnyValueUnitTest ‑ constructor(Double) creates an object with the expected value (normal cases)
com.google.firebase.dataconnect.AnyValueUnitTest ‑ constructor(List) creates an object with the expected value (edge cases)
com.google.firebase.dataconnect.AnyValueUnitTest ‑ constructor(List) creates an object with the expected value (normal cases)
com.google.firebase.dataconnect.AnyValueUnitTest ‑ constructor(Map) creates an object with the expected value (edge cases)
com.google.firebase.dataconnect.AnyValueUnitTest ‑ constructor(Map) creates an object with the expected value (normal cases)
…

com.google.firebase.vertexai.SchemaTests ‑ basic schema declaration
com.google.firebase.vertexai.SchemaTests ‑ full schema declaration
com.google.firebase.vertexai.StreamingSnapshotTests ‑ citation parsed correctly
com.google.firebase.vertexai.StreamingSnapshotTests ‑ empty content
com.google.firebase.vertexai.StreamingSnapshotTests ‑ http errors
com.google.firebase.vertexai.StreamingSnapshotTests ‑ image rejected
com.google.firebase.vertexai.StreamingSnapshotTests ‑ invalid api key
com.google.firebase.vertexai.StreamingSnapshotTests ‑ invalid json
com.google.firebase.vertexai.StreamingSnapshotTests ‑ long reply
com.google.firebase.vertexai.StreamingSnapshotTests ‑ malformed content
…

♻️ This comment has been updated with latest results.

[rlazo]

Please add a description and a clearer title

[rlazo]

Please update our tests to include better tests scenarios that really exercise the conversion API.