selftest/sstatetests: Extend to cover ERROR_QA/WARN_QA common issues

Now that adding new values to ERROR_QA doesn't invalidate tasks, add this
check to the selftests so that this functionality doens't regress in future.

(From OE-Core rev: 823b5f6cf64ad37ee68e6274c58823f7cc75ddf0)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/lib/oeqa/selftest/cases/sstatetests.py

@@ -474,6 +474,8 @@ TCLIBCAPPEND = \"\"
 MACHINE = \"qemuarm\"
 OLDEST_KERNEL = \"3.3.0\"
 BB_SIGNATURE_HANDLER = "OEBasicHash"
+ERROR_QA:append = " somenewoption"
+WARN_QA:append = " someotheroption"
 """
         self.sstate_common_samesigs(configA, configB, allarch=True)