Update to Unicode 15.0.0.
* lib/gen-uni-tables.c (is_property_default_ignorable_code_point):
Exclude 0x13439..0x1343F.
(get_lbp): Update such that unilbrk/lbrkprop.txt comes out as expected.
* All generated files under lib/uni* and tests/uni*: Regenerate.
* tests/uniname/NameAliases.txt: Update.
* tests/uniname/UnicodeData.txt: Update.
* tests/uninorm/NormalizationTest.txt: Update.
* tests/unigbrk/GraphemeBreakTest.txt: Update.
* tests/uniwbrk/WordBreakTest.txt: Update.
* tests/uniwidth/test-uc_width2.sh: Expect width 0 for the characters
0x0ECE, 0x10EFD..0x10EFF, 0x11241, 0x11F00..0x11F01, 0x11F36..0x11F3A,
0x11F40, 0x11F42, 0x13439..0x13440, 0x13447..0x13455, 0x1E08F,
0x1E4EC..0x1E4EF.
* All the affected modules: Bump required libunistring version.