- Remove use of (unused) `Cachable` module.
- Pass whether we're bottling to determine whether to create
reproducible SBOM or not. A reproducible SBOM omits the time and
compiler.
- Remove bottle information when bottling: we cannot know what e.g.
the checksum (and, with GitHub Packages, therefore also the download
location) will be before we've created the tarball contents.
- Always write a bottle on installation (unless we're bottling) to
provide new bottle information or freshen the existing one with the
information we stripped out for reproducibility e.g. the time and
compiler.
- Don't need to handle a `nil` `@source_modified_time` as it's always
set.
Fixes#17281
7461bf81a1