Skara doesn't handle tags with more than 4 digits in version number

To be able to react to new tags, Skara needs to know how to parse our tag formats. For this we have the OpenJDKTag class. The current pattern for Verona based versions in this class is limited to tags with 4 digit version numbers. This becomes a problem when a JDK release uses more of the up to 7 possible version digits currently allowed in mainline since JDK-8207849. We need to update the regex patterns used to parse tags.