AVRO-1897 ADDENDUM: Install all Java artifacts during test build.

The interop tests need the root POM installed to pass, so install all
build artifacts since other modules and tests depend on Java.
diff --git a/build.sh b/build.sh
index 14f3149..255e46a 100755
--- a/build.sh
+++ b/build.sh
@@ -40,7 +40,8 @@
     test)
       # run lang-specific tests
       (cd lang/java; ./build.sh test)
-      (cd lang/java; ./build.sh test; mvn install -pl tools  -am -DskipTests)
+      # install java artifacts required by other builds and interop tests
+      mvn install -DskipTests
       (cd lang/py; ./build.sh test)
       (cd lang/py3; ./build.sh test)
       (cd lang/c; ./build.sh test)