Fix missing inner comments in class expressions

[overlookmotel]

Fixes #13819.

Q	A
Fixed Issues?	Fixes #13819
Patch: Bug Fix?	Yes
Major: Breaking Change?	No
Minor: New Feature?	No
Tests Added + Pass?	Yes
Documentation PR Link	n/a
Any Dependency Changes?	No
License	MIT

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[fedeci]

Thanks!

[nicolo-ribaudo]

Thanks!

[JLHwung]

We may extend similar logic to other nodes, too:

To name a few:

class C {
  static /* 1 */ [a] = 1;
  * /* 2 */ [b]() {}
  async /* 3 */ [c]() {}
}
import "x" assert /* 4 */ { type: "json" }
async /* 5 */ (x) /* 6 */ => {}