RFR: mlrules: applying off-list suggestions

[Robin Westberg]

Hi all,

In this PR I'll collect the various updates to the jdk mailing list rules file that I'm receiving off-list (which is
perfectly fine, feel free to send plain suggestions my way and I'll collect them here!)

Best regards,
Robin

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Commit messages:
 - Remove jdwp from core-libs, remove nio-dev duplicates (alanb)
 - Simplify src/java.net.http (dfuchs)

Changes: https://git.openjdk.java.net/skara/pull/746/files
 Webrev: https://webrevs.openjdk.java.net/?repo=skara&pr=746&range=00
  Stats: 11 lines in 1 file changed: 0 ins; 10 del; 1 mod
  Patch: https://git.openjdk.java.net/skara/pull/746.diff
  Fetch: git fetch https://git.openjdk.java.net/skara pull/746/head:pull/746

PR: https://git.openjdk.java.net/skara/pull/746