build-unit-test-docker: upgrade googletest to 1.13.0

We've already incorporated a Yocto bump that moves to GTest 1.13,
so we might as well play along in the CI Docker container too.

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: I44b19e24dc2641ef6e1cba6eea416b4578931c96
diff --git a/scripts/build-unit-test-docker b/scripts/build-unit-test-docker
index b1173cc..e8e0ac8 100755
--- a/scripts/build-unit-test-docker
+++ b/scripts/build-unit-test-docker
@@ -132,9 +132,9 @@
             f"cp include/function2/function2.hpp {prefix}/include/function2/",
         ],
     ),
-    # release-1.12.1
+    # release-1.13.0
     "google/googletest": PackageDef(
-        rev="58d77fa8070e8cec2dc1ed015d66b454c8d78850",
+        rev="b796f7d44681514f58a683a3a71ff17c94edb0c1",
         build_type="cmake",
         config_env=["CXXFLAGS=-std=c++20"],
         config_flags=["-DTHREADS_PREFER_PTHREAD_FLAG=ON"],