Add `MathMLElement` interface and mixins `ElementCSSInlineStyle`, `HTMLOrForeignElement` #2679

Job	Run time
Taplo	5s
Rustfmt	11s
Check	1m 1s
Clippy	2m 50s
Clippy (project)	2m 26s
Clippy (web-sys)	2m 29s
Run wasm-bindgen crate tests (wasm-bindgen)	3m 53s
Run wasm-bindgen wasm test	1m 14s
Run wasm-bindgen crate tests (wasm-bindgen (serde-serialize))	1m 30s
Run wasm-bindgen crate tests (wasm-bindgen (enable-interning))	1m 18s
build_benchmarks	1m 6s
build_examples	3m 32s
build_nightly	1m 35s
Verify that web-sys is compiled correctly	47s
dist_linux_aarch64_gnu	3m 7s
dist_linux_x86_64_musl	2m 33s
dist_macos_aarch64	1m 17s
dist_macos_x86_64	1m 15s
dist_windows	3m 53s
doc_api	1m 20s
doc_book	8s
Check MSRV for CLI tools	31s
Check MSRV for libraries	1m 24s
Build and test the deno example	50s
Run native tests	2m 12s
Run wasm-bindgen crate tests with multithreading	1m 35s
Run UI compile-fail tests	47s
Run wasm-bindgen crate tests with externref feature	1m 16s
Run web-sys tests (with geckodriver)	22s
Run wasm-bindgen crate tests with multi-value feature	1m 41s
Run web-sys (all features) tests (with geckodriver)	2m 44s
Run web-sys (unstable, all features) tests (with geckodriver)	3m 9s
Run js-sys tests (with geckodriver)	1m 13s
Run js-sys (unstable) tests (with geckodriver)	1m 20s
Run wasm-bindgen-webidl tests (with geckodriver)	23s
Run webidl-tests tests (with geckodriver)	1m 30s
Run webidl-tests (unstable) tests (with geckodriver)	1m 11s
Run typescript-tests tests (with geckodriver)	1m 22s
test_nightly	41s
test_examples	1m 53s
deploy	39s
	1h 4m 13s

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