chore(examples): make build fail on any warning

Author: GuillaumeLagrange

examples/google_benchmark_bazel/BUILD.bazel

@@ -1,6 +1,7 @@
 cc_binary(
     name = "my_benchmark",
     srcs = glob(["*.cpp", "*.hpp"]),
+    copts = ["-Wall", "-Wextra", "-Werror"],
     deps = [
         "//google_benchmark:benchmark",
     ],

examples/google_benchmark_cmake/CMakeLists.txt

@@ -3,6 +3,11 @@ include(FetchContent)
 
 project(codspeed_picobench_compat VERSION 0.0.0 LANGUAGES CXX)
 
+# Treat warnings as errors
+if(CMAKE_CXX_COMPILER_ID MATCHES "GNU|Clang")
+    add_compile_options(-Wall -Wextra -Werror)
+endif()
+
 # On the small benchmarks of this repo, most of the benches will be optimized out, but this is expected.
 set(CMAKE_BUILD_TYPE RelWithDebInfo)