[jmc-graphics] RFR: 7574: Image for no System.gc release note

[Jeff Dinkins]

JMC-7574: Adding duke no-gc artwork

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Commit messages:
 - Create duke-no-gc.png

Changes: https://git.openjdk.java.net/jmc-graphics/pull/8/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jmc-graphics&pr=8&range=00
  Issue: https://bugs.openjdk.java.net/browse/JMC-7574
  Stats: 0 lines in 1 file changed: 0 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/jmc-graphics/pull/8.diff
  Fetch: git fetch https://git.openjdk.java.net/jmc-graphics pull/8/head:pull/8

PR: https://git.openjdk.java.net/jmc-graphics/pull/8