Remove the no_blank_lines_between_imports StyleCI rule.

This fixes the "The ... fixer cannot be enabled again because it has already been enabled" error.

Author: ShawnCZek

.styleci.yml

@@ -23,7 +23,6 @@ enabled:
   - no_blank_lines_after_phpdoc
   - no_blank_lines_after_return
   - no_blank_lines_after_throw
-  - no_blank_lines_between_imports
   - no_empty_phpdoc
   - no_empty_statement
   - no_extra_block_blank_lines