RFR: JDK-8297147: UnexpectedSourceImageSize test times out on slow machines when fastdebug is used

[Matthias Baesken]

The image related test UnexpectedSourceImageSize test introduced with https://bugs.openjdk.org/browse/JDK-8264666
sometimes times out on slow machines when fastdebug is used. This happens especially in 11 and 17; in 20 it seems to be a bit faster but we better change timeouts across releases.

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Commit messages:
 - JDK-8297147

Changes: https://git.openjdk.org/jdk/pull/11240/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=11240&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8297147
  Stats: 1 line in 1 file changed: 1 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/11240.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/11240/head:pull/11240

PR: https://git.openjdk.org/jdk/pull/11240