Replace the regex in `from_semconv_specs` with the `https://docs.rs/semver/latest/semver/` crate.

In the `weaver_semconv/src/registry.rs` method `from_semconv_specs` (see todo), we should use: https://docs.rs/semver/latest/semver/ and URL parser that can give us the last element of the path to send to the parser.

See this PR comment: https://github.com/open-telemetry/weaver/pull/400/#discussion_r1905412697