RFR: 8268915: WebKit build fails with Xcode 12.5

[Kevin Rushforth]

The JavaFX WebKit build fails with Xcode 12.5 + MacOS 11.3 SDK. This is related to the added C++20 support where some of the system include files now do `#include <version>`. Because the macOS file system is case insensitive, it matches a file named `VERSION` in the sqlite source directory. That file is just a plain text file (not used by our build at all) so the fix is to rename it to `VERSION.txt`. I've done a CI build on all three platforms. @jgneff has verified that renaming this file fixes the build for XCode 12.5.

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

Commit messages:
 - 8268915: WebKit build fails with Xcode 12.5

Changes: https://git.openjdk.java.net/jfx/pull/535/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jfx&pr=535&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8268915
  Stats: 0 lines in 1 file changed: 0 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/jfx/pull/535.diff
  Fetch: git fetch https://git.openjdk.java.net/jfx pull/535/head:pull/535

PR: https://git.openjdk.java.net/jfx/pull/535