RFR: 8297875: jar should not compress the manifest directory entry [v3]

[Liam Miller-Cushon]

> This causes jar to not compress the `META-INF/` directory entry, for consistency with the handling of other directory entries and compliance with `APPNOTE.TXT`, and for compatibility with other zip implementations.

Liam Miller-Cushon has updated the pull request incrementally with one additional commit since the last revision:

  Improve test

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/11441/files
  - new: https://git.openjdk.org/jdk/pull/11441/files/eaab9b03..9abb827f

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=11441&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=11441&range=01-02

  Stats: 33 lines in 1 file changed: 16 ins; 8 del; 9 mod
  Patch: https://git.openjdk.org/jdk/pull/11441.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/11441/head:pull/11441

PR: https://git.openjdk.org/jdk/pull/11441