RFR: 8297145: Add a @sealedGraph tag to ConstantDesc

[Per Minborg]

This PR proposes to opt in for graphic rendering of the sealed hierarchy of the 
ConstantDesc class.

Rendering capability was added via https://bugs.openjdk.org/browse/JDK-8295653


Here is how it would look like:

<img width="561" alt="ConstantDesc_SH" 
src="https://user-images.githubusercontent.com/7457876/202216017-ec996722-2956-4b0a-adb5-538bce12c135.png";>

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Commit messages:
 - Add a @sealedGraph tag to ConstantDesc

Changes: https://git.openjdk.org/jdk/pull/11187/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=11187&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8297145
  Stats: 1 line in 1 file changed: 1 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/11187.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/11187/head:pull/11187

PR: https://git.openjdk.org/jdk/pull/11187