Fix stack overflow in circular assignment declaration

[sandersn]

The declaration also needs to have multiple assignments so that it has a ValueModule flag.

The fix is to remove the possibly-circular call to getTypeofFuncClassEnumModule in the circularity-detection code path.

Fixes #33006

[sandersn]

This was introduced in #29335, but that test still passes with the fallback calls to getTypeOfFuncClassEnumModule removed.

[sandersn]

Oops, forgot that some tests were skipped. The tests do still fail.

[sandersn]

After some discussion, I don't think that #29335 is the correct fix; umdNamespaceMergedWithGlobalAugmentationIsNotCircular should still have an error, but a duplicate declaration error instead of a circular reference error.

[sandersn]

Since 3.7's beta ends today, I decided on a compromise fix, which is to avoid the fallback for symbols with flag Assignment. Those symbols will have already been checked using the JS code path, so aren't candidates for the special kind of merges handled in #29335.

Later I'll see whether I can catch the merge from #29335 in mergeSymbol during checker startup and issue an error there.

[sandersn]

@weswigham the React merge works because we allow aliases to merge with anything. If I resolveSymbol first and forbid merges between the source and the resolved alias, it breaks four tests and the breaks all look right to me. Opinions?