[code-reflection] RFR: Drop support for quoted structural lambdas [v2]

[Maurizio Cimadamore]

> The Babylon compiler extension supports structural quoting of lambdas. That is, if a lambda expression has `Quoted` target, then it must have explicit parameter types, and must be type-checked bottom up:
> 
> 
> Quoted q = () ->  {}
> 
> 
> Historically, `Quoted` was the first way to model quotable lambda expressions, and the language changes to support structural quotable lambdas were fairly invasive. Since then we moved to a more minimalistic approach which is similar to what we do for serializable lambdas: we use an intersection type cast to force quotability of the lambda expression:
> 
> 
> Runnable r = (Runnable & Quotable)() ->  {}
> 
> 
> Since the surface area of the `Quotable` support is much smaller (it shares the same machinery already available for serializable lambdas), it would be better to remove support for Quoted target when moving towards incubation.
> 
> This PR fixes all existing tests in langtools/JDK to use `Quotable` instead of `Quoted`. I did **not** check HAT, or `cr-examples`.

Maurizio Cimadamore has updated the pull request incrementally with one additional commit since the last revision:

  Re-add accidentally deleted test

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Changes:
  - all: https://git.openjdk.org/babylon/pull/667/files
  - new: https://git.openjdk.org/babylon/pull/667/files/e81dd7f2..bd6ddc10

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=babylon&pr=667&range=01
 - incr: https://webrevs.openjdk.org/?repo=babylon&pr=667&range=00-01

  Stats: 204 lines in 1 file changed: 204 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/babylon/pull/667.diff
  Fetch: git fetch https://git.openjdk.org/babylon.git pull/667/head:pull/667

PR: https://git.openjdk.org/babylon/pull/667