feat: New lint trait_no_longer_object_safe (#659)

* feat: adds new lint for trait object no longer safe

* feat: adds new lint for trait object no longer safe

* debugging test failures

* adjust output

* adjust query and output

* adjust doc

* chore: remove object safe trait tests

* chore: remove from macro

* chore: minor nit fixes for the lint query

---------

Co-authored-by: Predrag Gruevski <2348618+obi1kenobi@users.noreply.github.com>

src/lints/trait_no_longer_object_safe.ron

@@ -0,0 +1,49 @@
+SemverQuery(
+    id: "trait_no_longer_object_safe",
+    human_readable_name: "trait no longer object safe",
+    description: "A trait is no longer object safe, meaning it can no longer be used as `dyn Trait`.",
+    required_update: Major,
+    reference_link: Some("https://doc.rust-lang.org/stable/reference/items/traits.html#object-safety"),
+    query: r#"
+    {
+        CrateDiff {
+            baseline {
+                item {
+                    ... on Trait {
+                        visibility_limit @filter(op: "=", value: ["$public"]) @output
+                        object_safe @filter(op: "=", value: ["$true"])
+                        importable_path {
+                            path @output @tag
+                            public_api @filter(op: "=", value: ["$true"])
+                        }
+                    }
+                }
+            }
+            current {
+                item {
+                    ... on Trait {
+                        visibility_limit @filter(op: "=", value: ["$public"])
+                        name @output
+                        object_safe @filter(op: "!=", value: ["$true"])
+
+                        importable_path {
+                            path @filter(op: "=", value: ["%path"])
+                            public_api @filter(op: "=", value: ["$true"])
+                        }
+
+                        span_: span @optional {
+                            filename @output
+                            begin_line @output
+                        }
+                    }
+                }
+            }
+        }
+    }"#,
+    arguments: {
+        "public": "public",
+        "true": true,
+    },
+    error_message: "Trait is no longer object safe, which breaks `dyn Trait` usage.",
+    per_result_error_template: Some("trait {{trait_name}} in file {{span_filename}}:{{span_begin_line}}"),
+)