Prevent overwriting output dir to empty string

#KTIJ-921 Fixed

Co-authored-by: Alexander Udalov <Alexander.Udalov@jetbrains.com>

Merge-request: KT-MR-6183
Merged-by: Aleksei Cherepanov <aleksei.cherepanov@jetbrains.com>

compiler/cli/src/org/jetbrains/kotlin/cli/jvm/compiler/cliCompilerUtils.kt

@@ -115,7 +115,10 @@ fun writeOutput(
         return
     }
 
-    val outputDir = configuration.get(JVMConfigurationKeys.OUTPUT_DIRECTORY) ?: File(".")
+    val outputDir = configuration.get(JVMConfigurationKeys.OUTPUT_DIRECTORY)
+        ?.takeUnless { it.path.isBlank() }
+        ?: File(".")
+
     outputFiles.writeAll(outputDir, messageCollector, reportOutputFiles)
 }