Simplify mvn install commands with POM files

- Remove redundant -DgroupId, -DartifactId, -Dversion, -Dpackaging
- When using -DpomFile, Maven extracts metadata from POM automatically
- Cleaner commands that rely on POM for all artifact information

Author: trask

.github/unsafe/build-custom-armeria.sh

@@ -33,10 +33,6 @@ curl -sL -o "armeria-${VERSION}.pom" "https://repo1.maven.org/maven2/com/linecor
 # Install core JAR to Maven local repository with POM
 mvn install:install-file -q \
     -Dfile="$CORE_JAR" \
-    -DpomFile="armeria-${VERSION}.pom" \
-    -DgroupId=com.linecorp.armeria \
-    -DartifactId=armeria \
-    -Dversion="${VERSION}" \
-    -Dpackaging=jar
+    -DpomFile="armeria-${VERSION}.pom"
 
 echo "armeria ${VERSION} built and installed (UNSAFE disabled)."

.github/unsafe/build-custom-protobuf.sh

@@ -36,10 +36,6 @@ curl -sL -o "protobuf-java-${VERSION}.pom" "https://repo1.maven.org/maven2/com/g
 # Install to Maven local repository with POM
 mvn install:install-file -q \
     -Dfile="protobuf-java-${VERSION}.jar" \
-    -DpomFile="protobuf-java-${VERSION}.pom" \
-    -DgroupId=com.google.protobuf \
-    -DartifactId=protobuf-java \
-    -Dversion="${VERSION}" \
-    -Dpackaging=jar
+    -DpomFile="protobuf-java-${VERSION}.pom"
 
 echo "protobuf-java ${VERSION} built and installed (UNSAFE disabled)."