Add Constraint DOMException to handle the name conflict error in
`IDBDatabase::createObjectStore` method.
Testing: `./mach test-wpt tests/wpt/tests/IndexedDB/`, but it seems
there are many test failures even in main branch already ([related
comment](https://github.com/servo/servo/pull/37605#issuecomment-2993889163)).
Fixes: #37571
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Signed-off-by: iamlockon <xdddxyyyxzzz123@gmail.com>