POM: Move Checker Framework dependencies to submodules.

Change-Id: If611d49269cce036f0c81f6b1e95bccbb53a8882
diff --git a/jgvariant-ostree/pom.xml b/jgvariant-ostree/pom.xml
index d37bd5b..5968c5a 100644
--- a/jgvariant-ostree/pom.xml
+++ b/jgvariant-ostree/pom.xml
@@ -60,6 +60,20 @@
       <artifactId>xz</artifactId>
     </dependency>
 
+    <!-- Static analysis -->
+    <dependency>
+      <groupId>org.checkerframework</groupId>
+      <artifactId>checker</artifactId>
+      <scope>provided</scope>
+      <optional>true</optional>
+    </dependency>
+    <dependency>
+      <groupId>org.checkerframework</groupId>
+      <artifactId>checker-qual</artifactId>
+      <scope>provided</scope>
+      <optional>true</optional>
+    </dependency>
+
     <!-- Testing -->
     <dependency>
       <groupId>org.junit.jupiter</groupId>