This resolves https://github.com/llvm/llvm-project/issues/55475.
This adds a new AlignConsecutiveShortCaseStatements option in line with the existing AlignConsecutive* options , which when AllowShortCaseLabelsOnASingleLine is enabled will align the tokens after the case statement's colon. This also adds a AlignCaseColons option to allow aligning the case label colon itself rather than the token after it.
For the implementation, I tried re-using AlignTokens, however went with a custom alignment method instead since consecutive case labels require traversing scopes (which AlignTokens doesn't allow). Additionally, special casing was required to allow empty case labels to not break the alignment sequence.