[native_assets_builder] add WINDIR and SYSTEMDRIVE to allowed env list

[rainyl]

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Closes: #2077

As @dcharkes suggested, this PR add WINDIR and SYSTEMDRIVE to hookEnvironmentVariablesFilter at

native/pkgs/native_assets_builder/lib/src/build_runner/build_runner.dart

Lines 426 to 436 in 318f841

	static const hookEnvironmentVariablesFilter = {
	'ANDROID_HOME', // Needed for the NDK.
	'HOME', // Needed to find tools in default install locations.
	'PATH', // Needed to invoke native tools.
	'PROGRAMDATA', // Needed for vswhere.exe.
	'SYSTEMROOT', // Needed for process invocations on Windows.
	'TEMP', // Needed for temp dirs in Dart process.
	'TMP', // Needed for temp dirs in Dart process.
	'TMPDIR', // Needed for temp dirs in Dart process.
	'USER_PROFILE', // Needed to find tools in default install locations.
	};

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[dcharkes]

lgtm w comments

[dcharkes]

nit: Alphabetical sorting.

[rainyl]

Do you mean to sort the added 2 items or the whole set?

[dcharkes]

The whole set 👍

[rainyl]

Done 😄

[dcharkes]

No need for the CMAKE_TOOLCHAIN_FILE?

[rainyl]

No, it's not necessary, and usually CMAKE_TOOLCHAIN_FILE is not an env variable but a definition of cmake cli.

[github-actions]

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[coveralls]

coverage: 88.6%. remained the same
when pulling 7cdec59 on rainyl:hook-env-filter-cmake
into 318f841 on dart-lang:main.