Sccache passes content of response file directly to CreateProcess with msvc.

[ashwinbanwari]

I work with a large repo which uses response files to get around the Windows Server 32k character limit with CreateProcess. Sccache works well for us except when compiling object files that have an incredibly large amount of compiler options (mostly -IC (include directories)). We get the error [1] sccache: caused by: failed to spawn Command followed by the expanded command sccache tried to use to compile where it expanded the content of the response file instead of trying to use the original command.

Expected result: Sccache should try to compile using the compile command given to it where it references a response file and not try to compile with the expanded form of the command.