Separate java_tools into platform independent and prebuilt part.

java_tools is repository package containing tools needed during Java compilation: JavaBuilder, patches for Java compiler, ijar, singlejar, ...
Most of the files are jars with Java classes. java_tools are released for three platforms: linux, windows and darwin, however the only difference is in two binaries: ijar and singlejar.

This is part one of splitting java_tools and releasing split version (following PR makes use of released split version in Bazel)

Java_tools used to be released for multiple Java versions, but all the releases were the same except a some string substitutions in BUILD file. I changed to build only a single version, since it already supports Java from 8 to 14.

Changes:
- BUILD.java_tools is split into BUILD.java_tools_prebuilt (where the second contains prebuilt binaries)
- toolchain definitions are removed from BUILD.java_tools and will be added to tools/jdk/BUILD in the second part
- java_toolchain_default.bzl.java_tools is removed (default_java_toolchain.bzl will be updated with its features in the second part).
- src/BUILD: JAVA_VERSION is removed, targets used to build java_tools.zip are duplicated to build java_tools_prebuilt.zip (done some cleanup as well)
- upload_all_java_tools.sh and upload_java_tools.sh: used by Build kite, I removed java_version over the release, but kept it over tests (for different JDKs)
- create_java_tools_release.sh: used by the user in the release process - added platform independent part
- tests are updated to use platform independent and platform files, some tests had to be disabled and will be reenabled after the release

Closes #12546.

PiperOrigin-RevId: 344319092