Fix unused warnings in interfaces within the workspaces package

Author: ascopes

java-compiler-testing/src/main/java/io/github/ascopes/jct/workspaces/DirectoryBuilder.java

@@ -27,6 +27,7 @@
  * @author Ashley Scopes
  * @since 0.0.1
  */
+@SuppressWarnings("unused")
 @API(since = "0.0.1", status = Status.STABLE)
 public interface DirectoryBuilder {
 

java-compiler-testing/src/main/java/io/github/ascopes/jct/workspaces/FileBuilder.java

@@ -30,7 +30,7 @@
  * @since 0.0.1
  */
 @API(since = "0.0.1", status = Status.STABLE)
-@SuppressWarnings("unused")
+@SuppressWarnings({"unused", "UnusedReturnValue"})
 public interface FileBuilder {
 
   /**

java-compiler-testing/src/main/java/io/github/ascopes/jct/workspaces/PathRoot.java

@@ -32,6 +32,7 @@
  * @author Ashley Scopes
  * @since 0.0.1
  */
+@SuppressWarnings("unused")
 @API(since = "0.0.1", status = Status.STABLE)
 public interface PathRoot {