Remove spurious underscore in name of isolation tester on MSVC.

src/tools/msvc/Mkvcbuild.pm

@@ -272,7 +272,7 @@ sub mkvcbuild
     $pgregress_ecpg->AddDefine('FRONTEND');
     $pgregress_ecpg->AddReference($libpgport);
 
-    my $isolation_tester = $solution->AddProject('isolation_tester','exe','misc');
+    my $isolation_tester = $solution->AddProject('isolationtester','exe','misc');
     $isolation_tester->AddFile('src\test\isolation\isolationtester.c');
     $isolation_tester->AddFile('src\test\isolation\specparse.y');
     $isolation_tester->AddFile('src\test\isolation\specscanner.l');

src/tools/msvc/vcregress.pl

@@ -141,7 +141,7 @@ sub ecpgcheck
 sub isolationcheck
 {
 	chdir "../isolation";
-	copy("../../../$Config/isolation_tester/isolation_tester.exe",".");
+	copy("../../../$Config/isolationtester/isolationtester.exe",".");
     my @args = (
 				"../../../$Config/pg_isolation_regress/pg_isolation_regress",
 				"--psqldir=../../../$Config/psql",