Fix PHPCS Errors and warnings

PHPCS reported the following Errors and warnings

FILE: /variationcache/tests/src/Unit/VariationCacheTest.php
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FOUND 7 ERRORS AFFECTING 7 LINES
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 140 | ERROR | [x] Case breaking statements must be followed by a single blank line
 143 | ERROR | [x] Case breaking statements must be followed by a single blank line
 146 | ERROR | [x] Case breaking statements must be followed by a single blank line
 149 | ERROR | [x] Case breaking statements must be followed by a single blank line
 295 | ERROR | [ ] The array declaration extends to column 99 (the limit is 80). The array content should be split up over multiple lines
 426 | ERROR | [x] Parameter comment indentation must be 3 spaces, found 2 spaces
 431 | ERROR | [ ] Type hint "array" missing for $cache_id_parts
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PHPCBF CAN FIX THE 5 MARKED SNIFF VIOLATIONS AUTOMATICALLY