Raise limit on semicolons in lists

[1ec5]

As of #666, the style replaces at most two semicolons in a value list with a human-readable separator:

https://github.com/ZeLonewolf/openstreetmap-americana/blob/82f8de644a895246ea3182a318238af9cb8a5bfe/src/constants/label.js#L247-L253

This is based on the statistics in #666 (comment) and #666 (comment) that show a dropoff in the occurrence of more than one or two semicolons. However, in theory, some very prominent features could have multiple names to label. Unfortunately, the magnificent workaround for the lack of a string replacement expression operator requires recursion to produce the expression, and it isn’t possible to recurse indefinitely, let alone performantly.