Verifies issue creation for signature validation failure.
Issue reported: {
    issue : {
        code : SRIMessageSignatureIssue
        details : {
            sriMessageSignatureIssueDetails : {
                error : ValidationFailedSignatureMismatch
                integrityAssertions : [
                ]
                request : {
                    requestId : <string>
                    url : http://127.0.0.1:8000/inspector-protocol/resources/sri-message-signature-test.php?digest=sha-256%3D%3AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA%3D%3A&signature=signature%3D%3AgHim9e5Pk2H7c9BStOmxSmkyc8%2BioZgoxynu3d4INAT4dwfj5LhvaV9DFnEQ9p7C0hzW4o4Qpkm5aApd6WLLCw%3D%3D%3A&input=signature%3D%28%22unencoded-digest%22%3Bsf%29%3Bkeyid%3D%22JrQLj5P%2F89iXES9%2BvFgrIy29clF9CC%2FoPPsw3c5D0bs%3D%22%3Btag%3D%22sri%22
                }
                signatureBase : "unencoded-digest";sf: sha-256=:AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=: "@signature-params": ("unencoded-digest";sf);keyid="JrQLj5P/89iXES9+vFgrIy29clF9CC/oPPsw3c5D0bs=";tag="sri"
            }
        }
    }
}