Strip debug symbols from test binaries, to make the artifact smaller.

Uploading large artifacts is slow in github actions. To speed that up,
make the artifact smaller.

The code coverage tool doesn't require debug symbols, so remove them.

We've discussed doing the same for *all* binaries, but it's nice to
have debugging symbols for debugging purposes, and so that you get
more complete stack traces. The discussion is ongoing, but let's at
least do this for the test symbols now.

.github/workflows/build_and_test.yml

@@ -171,7 +171,10 @@ jobs:
             for bin in $test_exe_paths; do
               SRC=$bin
               DST=/tmp/neon/test_bin/$(basename $bin)
-              cp "$SRC" "$DST"
+
+              # We don't need debug symbols for code coverage, so strip them out to make
+              # the artifact smaller.
+              strip "$SRC" -o "$DST"
               echo "$DST" >> /tmp/coverage/binaries.list
             done
           fi