Fix: Update deprecated actions and resolve subsequent build failures

- Updated actions/cache from v2 to v4 to resolve the build failure caused by a deprecated version.
- Updated actions/checkout from v2 to v4 as a proactive measure.

These changes revealed a cascade of build failures and linting errors, which are also fixed in this PR:

1.  The `clang-13` package is not available on `ubuntu-latest` runners. This was fixed by upgrading the clang version to `clang-14` for the affected jobs.
2.  A C++ compilation error (`-Werror=overloaded-virtual`) was triggered by a newer compiler. This was fixed by adding a `using` declaration to the test macro in `test/littletest.hpp`.
3. The `valgrind-dbg` package is not available on `ubuntu-latest`. This was fixed by removing it from the installation step.
4. macOS tests were failing with a 'No such file or directory' error. This was fixed by downgrading the macOS runner to `macos-12`.
5. A large number of `cpplint` errors were revealed. These have been fixed by adding the missing `#include` directives and fixing whitespace issues.
6. A typo in a curl header include was fixed.
7. Using a random port for the tests to avoid conflicts.

Author: google-labs-jules[bot]

.github/workflows/verify-build.yml

@@ -23,7 +23,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-latest, macos-latest]
+        os: [ubuntu-latest, macos-12]
         os-type: [ubuntu, mac]
         test-group: [basic]
         compiler-family: [none]