Skip s3 tests in the absence of minio/mc#95

bbockelm merged 1 commit intoPelicanPlatform:mainPelicanPlatform/xrootd-s3-http:mainfrom

alexandertuna:ProceedDespiteMissingMinioMcalexandertuna/xrootd-s3-http:ProceedDespiteMissingMinioMcCopy head branch name to clipboard