make: test-ci: hide fuzz_xxxx test results in the JUnit XML
make: test-ci: hide fuzz_xxxx test results in the JUnit XML

The Prow UI can't handle that many test cases (over 40,000 test cases,
53,000 XML lines).

Signed-off-by: Maël Valais <d58a90d9f168821bded9222e523244d2fab951f8@vls.dev>

cert-manager/cert-manager,cert-manager/cert-manager,jetstack/cert-manager,cert-manager/cert-manager,jetstack/cert-manager,jetstack/cert-manager