config: do not warn about deprecated path if manually configured

CHANGELOG.md

···
 * `jj parallelize` can now parallelize groups of changes that _start_ with an
   immutable change, but do not contain any other immutable changes.
 
+* `jj` will no longer warn about deprecated paths on macOS if the configured
+  XDG directory is the deprecated one (~/Library/Application Support).
+
 ### Packaging changes
 
 * Due to the removal of the `libgit2` code path, packagers should

cli/src/config.rs

···
                     // Library/Preferences is supposed to be exclusively plists
                     s.data_dir()
                 })
+                .filter(|data_dir| {
+                    // User might've purposefully set their config dir to the deprecated one
+                    Some(data_dir) != config_dir.as_ref()
+                })
         } else {
             None
         };

cli/tests/test_config_command.rs

···
     [EOF]
     ");
 
+    // if XDG_CONFIG_HOME is ~/Library/Application Support,
+    // you shouldn't get a warning
+    let output = test_env.run_jj_with(|cmd| {
+        cmd.env_remove("JJ_CONFIG")
+            .env(
+                "XDG_CONFIG_HOME",
+                test_env.home_dir().join("Library/Application Support"),
+            )
+            .args(["config", "get", "foo.bar"])
+    });
+    insta::assert_snapshot!(output, @r"
+    Make sure I can pick this up
+    [EOF]
+    ");
+
     // if you set JJ_CONFIG, you shouldn't get a warning
     let output = test_env.run_jj_with(|cmd| {
         cmd.env("JJ_CONFIG", &user_config_path)