SemVer 2.0.0 requires a plus for build metadata.
https://semver.org/
`Build metadata MAY be denoted by appending a plus sign and a series of
dot separated identifiers immediately following the patch or pre-release
version. Identifiers MUST comprise only ASCII alphanumerics and hyphen
[0-9A-Za-z-]. Identifiers MUST NOT be empty. Build metadata SHOULD be
ignored when determining version precedence. Thus two versions that
differ only in the build metadata, have the same precedence. Examples:
1.0.0-alpha+001, 1.0.0+20130313144700, 1.0.0-beta+exp.sha.5114f85.`
Vasily
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