Build release builds with debug info

It is not possible to get anything sensible out of core dumps that do
not contain debug info, so make sure that release builds are built with
debug information by using `RelWithDebInfo`.

.github/gh_matrix_builder.py

@@ -92,7 +92,7 @@ def build_release_config(overrides):
     release_config = dict(
         {
             "name": "Release",
-            "build_type": "Release",
+            "build_type": "RelWithDebInfo",
             "tsdb_build_args": "-DWARNINGS_AS_ERRORS=ON -DREQUIRE_ALL_TESTS=ON",
             "coverage": False,
         }
@@ -120,7 +120,7 @@ def build_apache_config(overrides):
     apache_config = dict(
         {
             "name": "ApacheOnly",
-            "build_type": "Release",
+            "build_type": "RelWithDebInfo",
             "tsdb_build_args": "-DWARNINGS_AS_ERRORS=ON -DREQUIRE_ALL_TESTS=ON -DAPACHE_ONLY=1",
             "coverage": False,
         }