Enable ignoring tags

[rekmarks]

Currently, this action fails if tag validation fails, including if the most recent tag is not a valid SemVer version. We should add a configurable tag ignore list, probably via an action input, maybe using globs.

[Gudahtt]

What's the use case for this - when would an invalid tag exist? Just wondering if an ignore list is the best way to deal with this, v.s. skipping invalid tags when calculating the version or something like that.