runtime(java): Strive to remain compatible for at least Vim 7.0 (#14744) #16728

Job	Run time
linux (tiny, clang, native)	2m 47s
linux (tiny, gcc, native)	2m 42s
linux (normal, clang, native)	5m 46s
linux (normal, gcc, native)	5m 32s
linux (huge, clang, native)	9m 26s
linux (huge, gcc, native)	10m 45s
linux (tiny, clang, nogui)	2m 33s
linux (tiny, gcc, nogui)	2m 19s
linux (normal, gcc, i386, ./src/shadow)	6m 47s
macos (tiny, macos-12)	1m 13s
linux (huge, gcc, uchar, testgui, true, dynamic)	9m 34s
windows (HUGE, msvc, no, no, x64, stable)	6m 44s
macos (tiny, macos-14)	51s
windows (HUGE, mingw, yes, yes, x86, stable, yes)	11m 51s
linux (huge, clang, asan, 5.1)	16m 37s
macos (normal, macos-12)	7m 25s
windows (HUGE, msvc, no, yes, x86)	8m 33s
linux (huge, gcc, unittests, true)	2m 52s
macos (normal, macos-14)	4m 29s
windows (HUGE, mingw, yes, no, x64, yes)	9m 25s
linux (normal, gcc, vimtags)	2m 46s
macos (huge, macos-12)	13m 3s
windows (NORMAL, msvc, yes, no, x86)	6m 15s
windows (NORMAL, mingw, no, yes, x64)	9m 37s
macos (huge, macos-14)	13m 15s
windows (TINY, msvc, yes, yes, x64)	1m 45s
windows (TINY, mingw, no, no, x86)	2m 44s
	2h 57m 36s

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