JS: Move all integration tests.

We no longer need the platform-specific directories, so simplify the test organization.
If you don't want this change, just skip merging this PR.
It's purely optional.

The PR also deletes a spurious qlpack.yml that I missed when converting the tests to pytest.

javascript/ql/integration-tests/diagnostics/internal-error/diagnostics.expected

@@ -0,0 +1,14 @@
+{
+  "markdownMessage": "Internal error: com.semmle.util.exception.CatastrophicError: The TypeScript parser wrapper crashed with exit code 1",
+  "severity": "unknown",
+  "source": {
+    "extractorName": "javascript",
+    "id": "js/internal-error",
+    "name": "Internal error"
+  },
+  "visibility": {
+    "cliSummaryTable": true,
+    "statusPage": false,
+    "telemetry": true
+  }
+}

javascript/ql/integration-tests/diagnostics/internal-error/src/my_failure.ts

@@ -0,0 +1,17 @@
+type Output<K, S extends any[]> = {
+  (...args: S): any;
+};
+
+declare function createThing<K extends string, S extends any[]>(
+  type: K,
+  fn: (...args: S) => any
+): Output<K, S>;
+
+const one = createThing("one", () => ({}));
+
+const two = createThing("two", () => ({}));
+
+const three = createThing("three", (cursor: string) => null);
+const four = createThing("four", (error: number) => null);
+
+type Events = Array<typeof one | typeof two | typeof three | typeof four>;

javascript/ql/integration-tests/diagnostics/internal-error/test.py

@@ -0,0 +1,2 @@
+def test(codeql, javascript):
+    codeql.database.create(_assert_failure=True)

javascript/ql/integration-tests/diagnostics/internal-error/tsconfig.json

@@ -0,0 +1 @@
+{}

javascript/ql/integration-tests/diagnostics/syntax-error/bad.js

@@ -0,0 +1 @@
+4 %%% 5

javascript/ql/integration-tests/diagnostics/syntax-error/diagnostics.expected

@@ -0,0 +1,21 @@
+{
+  "location": {
+    "endColumn": 5,
+    "endLine": 1,
+    "file": "bad.js",
+    "startColumn": 5,
+    "startLine": 1
+  },
+  "markdownMessage": "A parse error occurred: `Unexpected token`. Check the syntax of the file. If the file is invalid, correct the error or [exclude](https://docs.github.com/en/code-security/code-scanning/automatically-scanning-your-code-for-vulnerabilities-and-errors/customizing-code-scanning) the file from analysis.",
+  "severity": "warning",
+  "source": {
+    "extractorName": "javascript",
+    "id": "js/parse-error",
+    "name": "Could not process some files due to syntax errors"
+  },
+  "visibility": {
+    "cliSummaryTable": true,
+    "statusPage": true,
+    "telemetry": true
+  }
+}

javascript/ql/integration-tests/diagnostics/syntax-error/test.py

@@ -0,0 +1,2 @@
+def test(codeql, javascript):
+    codeql.database.create()