Visual Studio 2022 17.1.0 ships a version of CMake whose generator
doesn't handle custom build commands correctly: instead of generating
one command per config that uses the correct $<CONFIG> value, it
generates multiple copies per configuration, one with each value of
$<CONFIG>, and only one of them is actually used. In practice, due to
the way VS resolves the incorrect duplication, it's always Release for a
flutter project, which causes the call to assemble to use the wrong
mode for debug builds, preventing them from launching.

This works around the generation bug, as a temporary measure until a
fixed version of Visual Studio is released, by rewriting the generated
project file to have the correct configuration value in each call.

This limits the workaround to just 17.1.0, as 17.1.1 should contain
a fix.

Fixes #97086

Pre-launch Checklist

• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• I read the Tree Hygiene wiki page, which explains my responsibilities.
• I read and followed the Flutter Style Guide, including Features we expect every widget to implement.
• I signed the CLA.
• I listed at least one issue that this PR fixes in the description above.
• I updated/added relevant documentation (doc comments with ///).
• I added new tests to check the change I am making, or this PR is test-exempt.
• All existing and new tests are passing.