generatePlotPNG函数里增加判断${TESTSRC}/plot.gp文件是否存在 #33

Job	Run time
Prerequisites / Prerequisites	43s
Prerequisites / Check Commit Message	0s
windows-x64 / build (debug)	33m 59s
linux-aarch64 / build (debug)	1s
linux-x64 / build (debug)	25m 37s
windows-x64 / build (release)	32m 2s
riscv64 / build (release)	24m 59s
linux-aarch64 / build (release)	1s
linux-x64 / build (release)	21m 23s
linux-x64 / test (jdk/tier1 part 1)	11m 45s
linux-x64 / test (jdk/tier1 part 2)	10m 34s
linux-x64 / test (jdk/tier1 part 3)	4m 47s
linux-x64 / test (langtools/tier1)	19m 32s
linux-x64 / test (hs/tier1 common)	2m 3s
linux-x64 / test (hs/tier1 compiler)	22m 1s
linux-x64 / test (hs/tier1 gc)	23m 1s
linux-x64 / test (hs/tier1 runtime)	7m 12s
linux-x64 / test (hs/tier1 serviceability)	3m 51s
linux-x64 / test (dragonwell/hs feature)	5m 7s
linux-x64 / test (dragonwell/jdk feature)	4m 38s
windows-x64 / test (jdk/tier1 part 1)	21m 34s
windows-x64 / test (jdk/tier1 part 2)	17m 19s
windows-x64 / test (jdk/tier1 part 3)	7m 59s
windows-x64 / test (langtools/tier1)	5s
windows-x64 / test (hs/tier1 common)	3m 54s
windows-x64 / test (hs/tier1 compiler)	4s
windows-x64 / test (hs/tier1 gc)	2s
windows-x64 / test (hs/tier1 runtime)	3s
windows-x64 / test (hs/tier1 serviceability)	3s
windows-x64 / test (dragonwell/hs feature)	4s
windows-x64 / test (dragonwell/jdk feature)	4s
Remove bundle artifacts	0s
linux-aarch64	0s
	5h 4m 27s

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