remove jdk.test.lib.FileInstaller action from graalunit tests

test/hotspot/jtreg/compiler/graalunit tests use jdk.test.lib.FileInstaller to copy ProblemList-graal.txt from test/hotspot/jtreg/ to the current working directory as ExcludeList.txt, and then run compiler.graalunit.common.GraalUnitTestLauncher w/ -exclude ExcludeList.txt.

j.t.l.FileInstaller actions aren't needed as c.g.c.GraalUnitTestLauncher interpeters `-exclude`'s value as path to file (as oppose to the file name in current directory), so we can use ${test.root}/ProblemList-graal.txt instead of ExcludeList.txt there.