Update build-sphinx.yml

remove redundant and failing date stamp

.github/workflows/build-sphinx.yml

@@ -50,5 +50,5 @@ jobs:
           echo "Empty README.md for documenation cache." > README.md
           echo "docs.cseptesting.org" > CNAME
           git add .
-          git commit -am "Updating pyCSEP docs for commit ${GITHUB_SHA} made on `date -d"@{SOURCE_DATE_EPOCH} --iso-8601=seconds` from ${GITHUB_REF} by ${GITHUB_ACTOR}"
+          git commit -am "Updating pyCSEP docs for commit ${GITHUB_SHA} from ${GITHUB_REF} by ${GITHUB_ACTOR}"
           git push deploy gh-pages --force