Use root db user by default

Dockerfile

@@ -4,15 +4,21 @@
 #
 # Cosmic JAR creation stage
 #
-FROM maven:3.9.1-eclipse-temurin-17 AS jar
+FROM maven:3.9.6-amazoncorretto-21 AS jar
 
 # Build in a separated location which won't have permissions issues.
 WORKDIR /opt/cosmic
+
 # Any changes to the pom will affect the entire build, so it should be copied first.
 COPY pom.xml ./pom.xml
+
 # Grab all the dependencies listed in the pom early, since it prevents changes to source code from requiring a complete re-download.
-# Skip compiling tests since we don't want all the dependecies to be downloaded.
-RUN mvn -f ./pom.xml clean dependency:go-offline -Dmaven.test.skip -T 1C
+# Skip compiling tests since we don't want all the dependencies to be downloaded.
+# RUN mvn -f ./pom.xml clean dependency:go-offline -Dmaven.test.skip -T 1C
+# TODO: The above command stopped working as of Java 21 upgrade due to:
+# Failed to execute goal org.apache.maven.plugins:maven-dependency-plugin:3.6.1:go-offline (default-cli) on project Cosmic: org.eclipse.aether.resolution.DependencyResolutionException: The following artifacts could
+# not be resolved: io.netty:netty-tcnative:jar:${os.detected.classifier}:2.0.65.Final (absent): Could not find artifact io.netty:netty-tcnative:jar:${os.detected.classifier}:2.0.65.Final in central (https://repo.maven.apache.org/maven2) -> [Help 1]
+
 # Source code changes may not change dependencies, so it can go last.
 # Skip compiling tests since we don't want all the dependecies to be downloaded for plugins.
 COPY src ./src
@@ -21,7 +27,7 @@ RUN mvn -f ./pom.xml clean package -Dmaven.test.skip -T 1C
 #
 # Server creation stage
 #
-FROM eclipse-temurin:17.0.6_10-jre
+FROM amazoncorretto:21
 
 # Host the server in a location that won't have permissions issues.
 WORKDIR /opt/server