Add GitHub team for maintaining fuzzers

Author: sethmlarson

.github/CODEOWNERS

@@ -132,7 +132,8 @@ Tools/c-analyzer/             @ericsnowcurrently
 Tools/check-c-api-docs/       @ZeroIntensity
 
 # Fuzzing
-Modules/_xxtestfuzz/          @ammaraskar
+Modules/_xxtestfuzz/                    @python/fuzzers
+.github/workflows/reusable-cifuzz.yml   @python/fuzzers
 
 # Limited C API & Stable ABI
 Doc/c-api/stable.rst          @encukou