Attempt to improve random connection errors in CI (#871)

This adds a Maven settings.xml file which contains the necessary settings to lower the TTL for connections in the connection pool used by Maven to download artifacts.

This is to work around an issue where Azure would silently terminate connections that have been idle for more than 4 minutes causing weird aborts in GitHub

java-devel/Dockerfile

@@ -47,6 +47,8 @@ RUN microdnf update && \
 
 ENV JAVA_HOME=/usr/lib/jvm/jre-${PRODUCT}
 
+COPY --chown=stackable:0 java-devel/stackable/settings.xml /stackable/.m2/settings.xml
+
 # Mitigation for CVE-2021-44228 (Log4Shell)
 # This variable is supported as of Log4j version 2.10 and
 # disables the vulnerable feature

java-devel/stackable/settings.xml

@@ -0,0 +1,29 @@
+<settings>
+  <profiles>
+    <profile>
+      <id>stackable</id>
+      <properties>
+        <!--
+        This is to work around an issue where Maven builds in Github Actions would randomly fail.
+        There is some evidence that points at Azure networking as the root cause where it closes idle connections (silently) after 4 minutes.
+        Maven would then sometimes reuse an "old" connection from its connection pool and would encounter issues due to these connection closures.
+        This patch changes the TTL for the connections to a lower value than 4 minutes (240s), the default is 300s (5min).
+
+        There are two properties here because sometimes in November 2023 the name was changed.
+        The new name will only take effect as of Maven 4, but it doesn't hurt to add it here already, therefore, we just add both properties here.
+        https://issues.apache.org/jira/browse/MRESOLVER-440
+        -->
+
+        <!-- Old name: maven-resolver 1.x, Maven 3.x -->
+        <aether.connector.http.connectionMaxTtl>30</aether.connector.http.connectionMaxTtl>
+
+        <!-- New name: maven-resolver 2.x, as of Maven 4.x -->
+        <aether.transport.http.connectionMaxTtl>30</aether.transport.http.connectionMaxTtl>
+      </properties>
+    </profile>
+  </profiles>
+  <activeProfiles>
+    <!--make the stackable profile active all the time -->
+    <activeProfile>stackable</activeProfile>
+  </activeProfiles>
+</settings>