Update Cargo and Clang support/tests for newer versions of the tools.

Review Request #12470 — Created July 13, 2022 and submitted — Latest diff uploaded


Since the development of the test suite for the current Cargo tool, the
Cargo's output has changed, and made more use of multiple spans to
represent output. This change improves the test suite, makes it more
compliant with the newer versions, and also enhances the span support to
do a more consistent job in getting the ideal span to show.

The Clang test suite has also been updated to fix an issue. Previously,
I had resolved an issue where some syntax error tests were triggering an
unwanted result from Clang (it saw the bad code as a lambda), but I
hadn't fixed this for all tests. Another test still had the old code.
This change updates that to use the same approach as the other test.

Upgraded Cargo. Verified unit tests pass.