Fix test script

Author: odersky

compiler/test/dotty/tools/dotc/CompilationTests.scala

@@ -41,7 +41,7 @@ class CompilationTests extends ParallelTesting {
     compileDir("../compiler/src/dotty/tools/dotc/util", defaultOptions) +
     compileDir("../compiler/src/dotty/tools/io", defaultOptions) +
     compileDir("../compiler/src/dotty/tools/dotc/core", noCheckOptions ++ classPath) +
-    compileFile("../tests/pos-special/i2797", defaultOptions) +
+    compileDir("../tests/pos-special/i2797", defaultOptions) +
     compileFile("../tests/pos/nullarify.scala", defaultOptions.and("-Ycheck:nullarify")) +
     compileFile("../tests/pos-scala2/rewrites.scala", scala2Mode.and("-rewrite")).copyToTarget() +
     compileFile("../tests/pos-special/t8146a.scala", allowDeepSubtypes) +