Minor change to resolve an issue that occurred when trying to build image CMSSW_11_1_0_Patatrack. Docker image name has to be lowercase, why I naively made the release to be given in lowercase. I then later turn it into uppercase when it is passed to the Dockerfile. In this case that lead to CMSSW_VERSION=CMSSW_11_1_0_PATATRACK to be passed to the Dockerfile as opposed to the expected version CMSSW_VERSION=CMSSW_11_1_0_Patatrack.
Fixed by asking for release in normal typing (with upper and lowercase chars) and then transforming it to lowercase for the image name. The change was tested yesterday and successfully built the image CMSSW_11_1_0_Patatrack.