Update to latest lints, require Dart 3.0 in pkg:protobuf #1250

Job	Run time
format_analyze; linux; Dart 3.1.0; PKG: protobuf; `dart analyze lib`, `dart analyze test`	21s
format_analyze; linux; Dart dev; PKG: benchmarks; `dart format --output=none --set-exit-if-change...	22s
format_analyze; linux; Dart dev; PKG: api_benchmark; `dart format --output=none --set-exit-if-cha...	27s
format_analyze; linux; Dart dev; PKG: protobuf; `dart format --output=none --set-exit-if-changed ...	25s
mono_repo self validate	17s
format_analyze; linux; Dart dev; PKG: protoc_plugin; `dart format --output=none --set-exit-if-cha...	32s
run_tests; linux; Dart 3.1.0; PKG: protoc_plugin; `./../tool/setup.sh`, `make protos`, `dart test`	44s
run_tests; linux; Dart 3.1.0; PKG: protobuf; `dart test`	26s
run_tests; linux; Dart dev; PKG: protobuf; `dart test`	29s
run_tests; osx; Dart 3.1.0; PKG: protobuf; `dart test`	1m 57s
run_tests; linux; Dart dev; PKG: protoc_plugin; `./../tool/setup.sh`, `make protos`, `dart test`	41s
run_tests; osx; Dart dev; PKG: protobuf; `dart test`	57s
run_tests; windows; Dart 3.1.0; PKG: protobuf; `dart test`	54s
run_tests; windows; Dart dev; PKG: protobuf; `dart test`	47s
run_legacy_tests; linux; Dart 3.1.0; PKG: protoc_plugin; `./../tool/setup.sh`, `make protos`, `da...	33s
	9m 52s

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