[tests] Split {language,language_2}/bit_operations_test.dart

[rakudrama]

bit_operations_test.dart does not compile for web targets due to non-web integer literals, and many of the tests won't pass since they reply on 64-bit operations.

The test should be split into three parts.

• bit_operations_common_test.dart for the small part that has common behavior between VM and web platforms
• bit_operations_vm_test.dart for the tests that rely on VM 64-bit integers
• bit_operations_web_test.dart for the tests that rely on web numbers

(It would also be reasonable for the common part to be a shared library).