fix(linter): remove invalid debug assersion, add test (#18819)

debug asserion could fail if the json was not a valid oxlintrc

Author: camc314

apps/oxlint/src/js_config.rs

@@ -84,7 +84,6 @@ fn parse_js_config_response(json: &str) -> Result<Vec<JsConfigResult>, Vec<OxcDi
                     let mut oxlintrc: Oxlintrc = match serde_json::from_value(entry.config) {
                         Ok(config) => config,
                         Err(err) => {
-                            debug_assert!(false, "All JS configs should be valid JSON");
                             errors.push(
                                 OxcDiagnostic::error(format!(
                                     "Failed to parse config from {}",

apps/oxlint/test/fixtures/js_config_invalid_property/files/oxlint.config.ts

@@ -0,0 +1,5 @@
+import { defineConfig } from "#oxlint";
+
+export default defineConfig({
+  rules: [],
+});

apps/oxlint/test/fixtures/js_config_invalid_property/files/test.js

@@ -0,0 +1 @@
+console.log("hi");

apps/oxlint/test/fixtures/js_config_invalid_property/output.snap.md

@@ -0,0 +1,14 @@
+# Exit code
+1
+
+# stdout
+```
+Failed to parse oxlint configuration file.
+
+  x Failed to parse config from <fixture>/files/oxlint.config.ts
+  note: invalid type: sequence, expected Record<string, SeverityConf | [SeverityConf, ...any[]]>
+```
+
+# stderr
+```
+```