PHPC-2654: Update to libmongoc 2.2.1

[alcaeus]

PHPC-2654. This update also fixes PHPC-2653.

[Copilot]

Pull request overview

This PR updates the MongoDB C driver (libmongoc) dependency from version 2.1.2 to 2.2.1, addressing PHPC-2654 and PHPC-2653. The update includes:

• Updated submodule reference to libmongoc 2.2.1
• Added new source files for OIDC cluster support (mongoc-cluster-oidc.c, mongoc-oidc-cache.c)
• Removed deprecated cursor source files (mongoc-cursor-find-cmd.c, mongoc-cursor-find-opquery.c, mongoc-cursor-legacy.c)

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
src/libmongoc	Updated submodule commit to libmongoc 2.2.1
sbom.json	Updated SBOM metadata with version 2.2.1 references and current timestamp
config.w32	Updated Windows build configuration with new source files for libmongoc 2.2.1
config.m4	Updated Unix build configuration with new source files and version requirements
.github/workflows/tests.yml	Updated CI pipeline to use libmongoc 2.2.1
.evergreen/config/templates/build/build-libmongoc.yml	Updated Evergreen build configuration to target 2.2.1 and r2.2 branch

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[jmikola]

Noted these are the defaults in libmongoc: https://github.com/mongodb/mongo-c-driver/blob/2.2.1/src/libmongoc/CMakeLists.txt#L754-L755

It doesn't seem ideal that libmongoc pollutes the handshake string with MONGOC_CXX_COMPILER_ID when it's "Unknown", though: https://github.com/mongodb/mongo-c-driver/blob/2.2.1/src/libmongoc/src/mongoc/mongoc-handshake.c#L494-L498

cc: @kevinAlbs

[kevinAlbs]

Suggest using an empty string instead of "Unknown" to signal "did not check". Filed CDRIVER-6175 to omit "CXX=" entirely if MONGOC_CXX_COMPILER_ID is empty.

Quoting mongodb/mongo-c-driver#2114:

If a C++ compiler is not found, CXX=Unknown is included. Alternatively: CXX could be omitted if not detected. But I expect it may help with analysis to easily distinguish between: "driver too old to check" and "checked and did not find".