fix(compiler-sfc): malformed filename on windows using path.join()

[b12k]

On Windows OS
"(path.posix || path)" still resolves to "path.posix"
which leads to a malformed "join()" filename path

Related to #9473

Reproduce (on Windows):

const path = require('path');

console.log({
    join: path.resolve(__filename, '..'), // ✅ >> "'C:\\code\\sandbox\\posix-path'"
    posixJoin: path.posix.join(__filename, '..'), // ❌ >> "."
    resolve: path.resolve(__filename, '..'), // ✅ >> "C:\\code\\sandbox\\posix-path"
    posixResolve: path.posix.resolve(__filename, '..'), // ✅ >> /code/sandbox/posix-path
})

Fix forces to use path.join() instead of path.posix.join() on Windows.

[haoqunjiang]

Do you have a runnable reproduction? I believe this has already been fixed in #9446
A full path with mixed / and \ should still be a valid Windows path.

[b12k]

I confirm that it's fixed in latest release.

Not fixed

[b12k]

@sodatea I re-opend the PR with this fix.
#9478