[Apple][NFC] Update macOS aligned version for lit config (#143576)

This updates the aligned version for version 26.

Note: This change is for correctness only and has no functional impact
currently. `get_macos_aligned_version` is currently only consumed when
substituting flags based on min version.

rdar://152851947

GitOrigin-RevId: 1c541aa9f9a2453324724bfb9d661bc672778d10
1 file changed