Fix Ruby MD5 not always being available in FIPS mode
Fix Ruby MD5 not always being available in FIPS mode

If Ruby is compiled against Amazon Linux's OpenSSL v1.0.2,
`Digest::MD5.new` fails with:

```
md5_dgst.c(82): OpenSSL internal error, assertion failed: Digest MD5
forbidden in FIPS mode!
```

However, this doesn't happen on RedHat or Ubuntu FIPS because the
OpenSSL `MD5_Init()` call isn't disabled in their OpenSSL v1.1 FIPS
libraries. Instead, it is disabled via the `EVP_DigestInit_ex()` call,
which is why `OpenSSL::Digest::MD5.new` fails but `Digest::MD5.new`
works.

In either case, we should just use the Ruby MD5 implementation until
Chef completely removes the use of MD5.

Relates to https://gitlab.com/gitlab-org/omnibus-gitlab/-/issues/7182

Changelog: fixed

gitlabhq/omnibus-gitlab,gitlabhq/omnibus-gitlab,gitlabhq/omnibus-gitlab,gitlabhq/omnibus-gitlab