RFR: 8248: [Accessibility] Low Contrast in High Contrast mode on Stacktrace View

[Suchita Chaturvedi]

This PR is to fix the accessibility issue for High Contrast mode. Stracktrace View was not readable at all in dark mode.

Before the fix:
<img width="959" alt="image" src="https://github.com/user-attachments/assets/f12f1b7d-aa8a-4cce-8e0c-7731d5f9cc96">

After the fix:
<img width="959" alt="image" src="https://github.com/user-attachments/assets/8f7be98a-206b-4758-a1c2-8971d7ab1c55">

-------------

Commit messages:
 - 8248: [Accessibility] Low Contrast in High Contrast mode on Stacktrace View

Changes: https://git.openjdk.org/jmc/pull/580/files
  Webrev: https://webrevs.openjdk.org/?repo=jmc&pr=580&range=00
  Issue: https://bugs.openjdk.org/browse/JMC-8248
  Stats: 51 lines in 3 files changed: 42 ins; 0 del; 9 mod
  Patch: https://git.openjdk.org/jmc/pull/580.diff
  Fetch: git fetch https://git.openjdk.org/jmc.git pull/580/head:pull/580

PR: https://git.openjdk.org/jmc/pull/580