[jdk17u-dev] RFR: 8347300: Don't exclude the "PATH" var from the environment when running app launchers in jpackage tests

[Goetz Lindenmaier]

Backport for the same reasons as for the backport to 21, now to 17.
Based of the change pushed in 21.

I had to resolve CfgFile.java, the code in 17 looks slightly different.
Further I omitted the changes to LauncherAsServiceVerifier.java
because that file is not in 17.

I had to do some further adaptions to make the changes compile.
The code uses some methods only in 21 (List.reversed() and List.getFirst()). 
I replaced these by plain coding.
In 21, record Comm has been moved out of TKIT, this is needed now in 17, 
too.  
Find these changes in the second commit.

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Commit messages:
 - Test adaptions to make it compile
 - backport 8347300 from 21

Changes: https://git.openjdk.org/jdk17u-dev/pull/4173/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=4173&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8347300
  Stats: 321 lines in 10 files changed: 239 ins; 26 del; 56 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/4173.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/4173/head:pull/4173

PR: https://git.openjdk.org/jdk17u-dev/pull/4173