chore: Add tooling to detect missing specification tests

[justinabrahms]

This PR

This adds a tool so we know which spec tests are missing. It is nearly identical to https://github.com/open-feature/java-sdk/blob/main/spec_finder.py, save the regexps.

How to test

$ python spec_finder.py
In the spec, but not in our tests: 
  1.1.1: The API, and any state it maintains SHOULD exist as a global singleton, even in cases wherein multiple versions of the API are present at runtime.
  1.1.2.1: The API MUST define a provider mutator, a function to set the default provider, which accepts an API-conformant provider implementation.
  1.1.2.2: The provider mutator function MUST invoke the initialize function on the newly registered provider before using it to resolve flag values.
  1.1.2.3: The provider mutator function MUST invoke the shutdown function on the previously registered provider once it's no longer being used to resolve flag values.
  1.1.3: The API MUST provide a function to bind a given provider to one or more client names. If the client-name already has a bound provider, it is overwritten with the new mapping.
  1.1.4: The API MUST provide a function to add hooks which accepts one or more API-conformant hooks, and appends them to the collection of any previously added hooks. When new hooks are added, previously added hooks are not removed.
  1.1.5: The API MUST provide a function for retrieving the metadata field of the configured provider.
  1.1.6: The API MUST provide a function for creating a client which accepts the following options:  - name (optional): A logical string identifier for the client.
  1.1.7: The client creation function MUST NOT throw, or otherwise abnormally terminate.
  1.1.8: The API SHOULD provide functions to set a provider and
....a bunch more....

[beeme1mr]

I'm a bit bummed you didn't write this in Rust.

[sheepduke]

Just one question: How do you handle the Conditions in the spec? :-)

[justinabrahms]

@sheepduke https://github.com/open-feature/java-sdk/blob/main/src/test/java/dev/openfeature/sdk/FlagEvaluationSpecTest.java#L318-L325

All specification items need to be accounted for. For some, I annotate a bare test w/ a name that explains why this doesn't apply to us.

[sheepduke]

@sheepduke https://github.com/open-feature/java-sdk/blob/main/src/test/java/dev/openfeature/sdk/FlagEvaluationSpecTest.java#L318-L325

All specification items need to be accounted for. For some, I annotate a bare test w/ a name that explains why this doesn't apply to us.

That makes sense. Thank you!