build(test): migrate pom.xml Surefire env from DO_NOT_TRACK=1 to AXONFLOW_TELEMETRY=off

Caught in deep code review of the DNT-removal sweep. The Surefire test
plugin's <environmentVariables> block was still setting DO_NOT_TRACK=1
to suppress telemetry during local mvn test / IDE Maven test runs.

After the production code stops honoring DNT, this becomes a no-op
for telemetry suppression — so every local mvn test run would have
fired real pings to checkpoint.getaxonflow.com. Flipping to
AXONFLOW_TELEMETRY=off restores the suppression on the same path the
CI workflows already migrated to.

Author: saurabhjain1592

pom.xml

@@ -193,7 +193,7 @@
                         <exclude>**/*IntegrationTest.java</exclude>
                     </excludes>
                     <environmentVariables>
-                        <DO_NOT_TRACK>1</DO_NOT_TRACK>
+                        <AXONFLOW_TELEMETRY>off</AXONFLOW_TELEMETRY>
                     </environmentVariables>
                 </configuration>
             </plugin>