Update declarative config file format version

Author: trask

instrumentation/resources/library/src/test/java/io/opentelemetry/instrumentation/resources/internal/DeclarativeConfigTest.java

@@ -24,7 +24,7 @@ class DeclarativeConfigTest {
   @Test
   void endToEnd() {
     String yaml =
-        "file_format: 0.1\n"
+        "file_format: 0.3\n"
             + "resource:\n"
             + "  attributes:\n"
             + "    - name: service.name\n"