RFR: 8255572: Axis does not compute preferred height properly when autoRanging is off

[Jonathan Vusich]

As noted in the corresponding JBS issue, `Axis` does not properly compute its preferred height when `autoRanging` is turned off. The simplest fix seems to be changing `CategoryAxis` so that `tickLabelRotation` is set to 90 degrees if there is not enough room for the category labels to layout horizontally. This fixes the fact that the axis labels are truncated and also ensures that the chart does not leave unused space from the layout calculations. `CategoryAxis` is already setting the `categorySpacing` property when `autoRanging` is off, so this seems to be an appropriate fix.

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Commit messages:
 - Added fix and test

Changes: https://git.openjdk.java.net/jfx/pull/342/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jfx&pr=342&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8255572
  Stats: 90 lines in 2 files changed: 90 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/jfx/pull/342.diff
  Fetch: git fetch https://git.openjdk.java.net/jfx pull/342/head:pull/342

PR: https://git.openjdk.java.net/jfx/pull/342