RFR: 8292944: Noisy output when running make help the first time

[Magnus Ihse Bursie]

>From the bug report:
Running make help after configuring produces a lot of noisy output from make before the actual help text is displayed.

Reproducer:

* bash ./configure --with-boot-jdk=... --with-devkit=...
* make help

It only happens on the first invocation of make help, subsequent runs only display the actual help text. 

What happened was that the module-deps.gmk and find-test.gmk files where generated at an inopportune moment.

Note that this PR is dependent on https://github.com/openjdk/jdk/pull/23355 (I hope I got the Skara incantations right for that...)

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Depends on: https://git.openjdk.org/jdk/pull/23355

Commit messages:
 - 8292944: Noisy output when running make help the first time

Changes: https://git.openjdk.org/jdk/pull/23357/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=23357&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8292944
  Stats: 17 lines in 4 files changed: 11 ins; 0 del; 6 mod
  Patch: https://git.openjdk.org/jdk/pull/23357.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/23357/head:pull/23357

PR: https://git.openjdk.org/jdk/pull/23357