test: add test for ApiTracerContextTest

Author: diegomarquezp

gax-java/gax/src/test/java/com/google/api/gax/tracing/ApiTracerContextTest.java

@@ -74,6 +74,17 @@ void testGetAttemptAttributes_artifact() {
         .containsEntry(ObservabilityAttributes.ARTIFACT_ATTRIBUTE, "test-artifact");
   }
 
+  @Test
+  void testGetAttemptAttributes_version() {
+    LibraryMetadata libraryMetadata =
+        LibraryMetadata.newBuilder().setLibraryVersion("1.2.3").build();
+    ApiTracerContext context =
+        ApiTracerContext.newBuilder().setLibraryMetadata(libraryMetadata).build();
+    Map<String, Object> attributes = context.getAttemptAttributes();
+
+    assertThat(attributes).containsEntry(ObservabilityAttributes.VERSION_ATTRIBUTE, "1.2.3");
+  }
+
   @Test
   void testGetAttemptAttributes_fullMethodName_noTransport_notPresent() {
     ApiTracerContext context =
@@ -125,7 +136,11 @@ void testGetAttemptAttributes_empty() {
   @Test
   void testGetAttemptAttributes_emptyStrings() {
     LibraryMetadata libraryMetadata =
-        LibraryMetadata.newBuilder().setRepository("").setArtifactName("").build();
+        LibraryMetadata.newBuilder()
+            .setRepository("")
+            .setArtifactName("")
+            .setLibraryVersion("")
+            .build();
     ApiTracerContext context =
         ApiTracerContext.newBuilder()
             .setLibraryMetadata(libraryMetadata)