RFR: 7903929: Improve component layout in ChoiceQuestionRenderer and ChoiceArrayQuestionRenderer

[Dmitry Bessonov]

The ChoiceQuestionRenderer and ChoiceArrayQuestionRenderer classes contain a complex layout of the components which represent selectable options. This layout is based on JTable used as a container and this over-complicates navigation with keyboard and proper rendering.

Instead of JTable, a standard approach to layout using panels could be used.

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Commit messages:
 - 7903892: JT Harness - cannot do a selection in a group of components via keyboard

Changes: https://git.openjdk.org/jtharness/pull/91/files
  Webrev: https://webrevs.openjdk.org/?repo=jtharness&pr=91&range=00
  Issue: https://bugs.openjdk.org/browse/CODETOOLS-7903929
  Stats: 262 lines in 2 files changed: 10 ins; 232 del; 20 mod
  Patch: https://git.openjdk.org/jtharness/pull/91.diff
  Fetch: git fetch https://git.openjdk.org/jtharness.git pull/91/head:pull/91

PR: https://git.openjdk.org/jtharness/pull/91