Improve search filter by taking space in file path into account

What does this MR do?

This MR changes how to tokenize the input search strings. Before this change, we split the string by whitespace. If whitespace exists in a path of a file, for example foo path:"my test.txt", it produces ["foo", 'path:"my', 'test.txt"']. It's very likely it won't find a path matching "my.

The change is to not break words inside double-quotes.

This is related to #281677 (closed)

Screenshots (strongly suggested)

Does this MR meet the acceptance criteria?

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