Consistent use of double quotes arround env vars

... except arround the ${plugins} variabel used in the for loop because
that would prevent word split and make the loop execute only once,
instead of once per word (ie. plugin)

Author: miguelaferreira

dockerhub/entrypoint.sh

@@ -2,25 +2,25 @@
 
 set -e
 
-echo ${KUBE_CONFIG_DATA} | base64 -d > kubeconfig
+echo "${KUBE_CONFIG_DATA}" | base64 -d > kubeconfig
 export KUBECONFIG="${PWD}/kubeconfig"
-chmod 600 ${PWD}/kubeconfig
+chmod 600 "${PWD}/kubeconfig"
 
 if [[ -n "${INPUT_PLUGINS// /}" ]]
 then
-    plugins=$(echo ${INPUT_PLUGINS} | tr ",")
+    plugins="$(echo "${INPUT_PLUGINS}" | tr ",")"
 
     for plugin in ${plugins}
     do
         echo "installing helm plugin: [${plugin}]"
-        helm plugin install ${plugin}
+        helm plugin install "${plugin}"
     done
 fi
 
 echo "running entrypoint command(s)"
 
 response=$(sh -c " ${INPUT_COMMAND}")
 
-echo "response<<EOF" >> ${GITHUB_OUTPUT}
-echo "$response" >> ${GITHUB_OUTPUT}
-echo "EOF" >> ${GITHUB_OUTPUT}
+echo "response<<EOF" >> "${GITHUB_OUTPUT}"
+echo "$response" >> "${GITHUB_OUTPUT}"
+echo "EOF" >> "${GITHUB_OUTPUT}"