Make image variable

action/Dockerfile

@@ -1,4 +1,5 @@
-FROM gableroux/unity3d:2019.2.11f1
+ARG IMAGE
+FROM $IMAGE
 
 LABEL "com.github.actions.name"="Unity - Test runner"
 LABEL "com.github.actions.description"="Run tests for any Unity project."

action/entrypoint.sh

@@ -29,6 +29,12 @@ esac
 # The following tests are 2019 mode (requires Unity 2019.2.11f1 or later)
 # Reference: https://docs.unity3d.com/2019.3/Documentation/Manual/CommandLineArguments.html
 
+#
+# Display the unity version
+#
+
+echo "Using Unity version \"$UNITY_VERSION\" to test."
+
 #
 # Overall info
 #