fixed different handling of egrep between mac and ubuntu

.github/workflows/debug.yml

@@ -28,9 +28,6 @@ jobs:
 
       - name: "install ghostscript"
         run: sudo apt-get install -y ghostscript
-        
-      - name: "install zip"
-        run: sudo apt-get install -y zip
       
       ###### multiple options for a TeX environment
       #   ##

.github/workflows/release.yaml

@@ -18,9 +18,6 @@ jobs:
         # Checks-out your repository under $GITHUB_WORKSPACE, so your job can access it
         uses: actions/checkout@v2
 
-      - name: "install zip"
-        run: sudo apt-get install -y zip
-
         ## create varibale ${{ steps.tag.outputs.tag }}
       - name: "get tag"
         id: tag

create-release.sh

@@ -107,9 +107,12 @@ check_zip
 
 ## extract DATE from versionhistory.tex
 LINE=$(grep "vhEntry{$VERSION_NUM" doc/versionhistory.tex)
-DATEISO=$(echo $LINE | egrep -o '\d{4}-(0[1-9]|1[0-2])-(0[1-9]|[12][0-9]|3[01])')
+DATEISO=$(echo $LINE | egrep -o '[0-9]{4}-(0[1-9]|1[0-2])-(0[1-9]|[12][0-9]|3[01])')
 # DATE=$(echo $DATEISO | sed -e "s|-|\\\/|g") # with escape character for sed
 # DATE=$(date "+%Y\/%m\/%d") # with escape character for sed
+if [ $verbose = 1 ]; then
+  echo "The date $DATEISO was extracted from versionhistory.tex."
+fi
 
 ## create backup-file und update VERSIONDATE in tikz-trackschematic.sty
 sed -i '.backup' -e "s|VERSIONDATE|$DATEISO|g" src/tikz-trackschematic.sty