Prepare 2.6.0.dev2

[Eric-Arellano]

[ci skip-rust]

[Eric-Arellano]

Internal

• Minimize RuleRunner parallelism. (#12206)

• [internal] Increase engine build parallelism, and include arch in fingerprint. (#12201)

• Fix engine_pyo3/build.rs missing clippy. (#12196)

• Include the arch in the venv directory path. (#12192)

• [internal] Port PyNailgunClient to PyO3 (#12181)

• Start incremental migration from rust-cpython to PyO3 (#12110)

• Fix risk of dangling workunits by using in_workunit! macro (#11759)

• Add minimal javac rules and tests. (#12005)

• Stop using pint to parse --pantsd-max-memory-usage due to performance regression (#12176)

• [internal] Hotfix release.sh breaking when building with Python 3.8 (#12175)

• Prepare 2.5.1rc2 (#12173)

• [internal] Use long-form arguments for release.sh (#12017)

• [internal] upgrade toolchain pants plugin to 0.12.0 (#12168)

• Prepare 2.2.4rc0 (#12170)

• Prepare 2.3.3rc0 (#12171)

• Prepare 2.4.2rc1 (#12172)

• Explain Interns::key_get Key Debug sensitivity. (#12167)

• Use relaxed ordering for pure counter. (#12166)

• Stabilize pex_test.py. (#12155)

• Temporarily fix a test that relies on the state of the world. (#12153)