[test] Add test for broken lambda capturing

SSA redefines context refs which breaks our inference. The correct fix here is 
to not overwrite context refs in EnterSSA.

compiler/forget/src/__tests__/fixtures/hir/_bug.capturing-func-simple-alias.expect.md

@@ -0,0 +1,40 @@
+
+## Input
+
+```javascript
+function component(a) {
+  let x = { a };
+  let y;
+  (function () {
+    y = x;
+  })();
+  mutate(y);
+  return y;
+}
+
+```
+
+## Code
+
+```javascript
+function component(a) {
+  const $ = React.unstable_useMemoCache();
+  const c_0 = $[0] !== a;
+  let x;
+  if (c_0) {
+    x = { a: a };
+    $[0] = a;
+    $[1] = x;
+  } else {
+    x = $[1];
+  }
+  const y = undefined;
+  (function () {
+    y = x;
+  })();
+  mutate(y);
+  return y;
+}
+
+```
+      

compiler/forget/src/__tests__/fixtures/hir/_bug.capturing-func-simple-alias.js

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+function component(a) {
+  let x = { a };
+  let y;
+  (function () {
+    y = x;
+  })();
+  mutate(y);
+  return y;
+}