C-Blosc2: Fuzzer Tests (#42881)

The fuzzer tests are a bit flaky and have linker issues on
clang. We generally only should build them in testing.

var/spack/repos/builtin/packages/c-blosc2/package.py

@@ -69,6 +69,7 @@ def cmake_args(self):
             self.define("BUILD_TESTS", self.run_tests),
             self.define("BUILD_BENCHMARKS", self.run_tests),
             self.define("BUILD_EXAMPLES", self.run_tests),
+            self.define("BUILD_FUZZERS", self.run_tests),
         ]
 
         return args