Fix tdz checks in transform-block-scoping plugin (#9498)

* Better tdz tests

- Use jest's expect.toThrow/expect.not.toThrow
- Add input/output tests

* Fix basic tdz (a = 2; let a)

Fixes #6848

* Make _guessExecutionStatusRelativeTo more robust

* Add tests

* Return less "unkown" execution status

* "function" execution status does not exist

* Fix recursive functions

* Update helper version

* "finally" blocks are always executed

* Typo

packages/babel-plugin-transform-block-scoping/test/fixtures/tdz/function-ref/input.js

@@ -0,0 +1,3 @@
+function f() { x }
+maybeCall(f);
+let x;

packages/babel-plugin-transform-block-scoping/test/fixtures/tdz/function-ref/output.js

@@ -0,0 +1,9 @@
+var x = babelHelpers.temporalUndefined;
+
+function f() {
+  babelHelpers.temporalRef(x, "x");
+}
+
+maybeCall(f);
+x = void 0;
+void 0;