Remove random password in Dockerfiles (#15362)

* Remove random password of git user in dockerfile

* Disable git user account in rootless dockerfile

Dockerfile

@@ -53,7 +53,7 @@ RUN addgroup \
     -u 1000 \
     -G git \
     git && \
-  echo "git:$(dd if=/dev/urandom bs=24 count=1 status=none | base64)" | chpasswd
+  echo "git:*" | chpasswd -e
 
 ENV USER git
 ENV GITEA_CUSTOM /data/gitea

Dockerfile.rootless

@@ -46,8 +46,7 @@ RUN addgroup \
     -s /bin/bash \
     -u 1000 \
     -G git \
-    git && \
-  echo "git:$(dd if=/dev/urandom bs=24 count=1 status=none | base64)" | chpasswd
+    git
 
 RUN mkdir -p /var/lib/gitea /etc/gitea
 RUN chown git:git /var/lib/gitea /etc/gitea