RFR: 8283703: Add sealed modifier to java.awt.geom.Path2D

[Phil Race]

JDK 17 delivered JEP 409: Sealed Classes : https://openjdk.java.net/jeps/409
In essence this JEP allows a class to limit which classes can subclass it.

Path2D can be sealed because no code outside the package can sub-class it directly.

However the extant subclasses need to be made non-sealed as they can be sub-classed.

jtreg tests and JCK API tests pass.

CSR here : https://bugs.openjdk.java.net/browse/JDK-8284031

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Commit messages:
 - 8283703: Add sealed modifier to java.awt.geom.Path2D

Changes: https://git.openjdk.java.net/jdk/pull/8048/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=8048&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8283703
  Stats: 5 lines in 1 file changed: 2 ins; 0 del; 3 mod
  Patch: https://git.openjdk.java.net/jdk/pull/8048.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/8048/head:pull/8048

PR: https://git.openjdk.java.net/jdk/pull/8048