RFR: 7903426: jcstress: Polish README.md [v2]

[Johnny Lim]

> This PR polishes the `README.md` file a bit.

Johnny Lim has updated the pull request incrementally with one additional commit since the last revision:

  Apply suggestions

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Changes:
  - all: https://git.openjdk.org/jcstress/pull/131/files
  - new: https://git.openjdk.org/jcstress/pull/131/files/cbc935a4..aa63fdf3

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jcstress&pr=131&range=01
 - incr: https://webrevs.openjdk.org/?repo=jcstress&pr=131&range=00-01

  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jcstress/pull/131.diff
  Fetch: git fetch https://git.openjdk.org/jcstress pull/131/head:pull/131

PR: https://git.openjdk.org/jcstress/pull/131