CTestCommandLine tests: Make sure to test successful run

Add a DartConfiguration.tcl file in two places, so that testing the
generated Text.xml file does not depend on output in stderr.

Tests/RunCMake/CTestCommandLine/RunCMakeTest.cmake

@@ -355,6 +355,9 @@ function(run_TestOutputSize)
   set(RunCMake_TEST_NO_CLEAN 1)
   file(REMOVE_RECURSE "${RunCMake_TEST_BINARY_DIR}")
   file(MAKE_DIRECTORY "${RunCMake_TEST_BINARY_DIR}")
+  file(WRITE "${RunCMake_TEST_BINARY_DIR}/DartConfiguration.tcl" "
+BuildDirectory: ${RunCMake_TEST_BINARY_DIR}
+")
   file(WRITE "${RunCMake_TEST_BINARY_DIR}/CTestTestfile.cmake" "
   add_test(PassingTest \"${CMAKE_COMMAND}\" -E echo PassingTestOutput)
   add_test(FailingTest \"${CMAKE_COMMAND}\" -E no_such_command)
@@ -375,6 +378,9 @@ function(run_TestOutputTruncation mode expected)
   set(TRUNCATED_OUTPUT ${expected})  # used in TestOutputTruncation-check.cmake
   file(REMOVE_RECURSE "${RunCMake_TEST_BINARY_DIR}")
   file(MAKE_DIRECTORY "${RunCMake_TEST_BINARY_DIR}")
+  file(WRITE "${RunCMake_TEST_BINARY_DIR}/DartConfiguration.tcl" "
+BuildDirectory: ${RunCMake_TEST_BINARY_DIR}
+")
   file(WRITE "${RunCMake_TEST_BINARY_DIR}/CTestTestfile.cmake" "
   add_test(Truncation_${mode} \"${CMAKE_COMMAND}\" -E echo 123456789)
 ")

Tests/RunCMake/CTestCommandLine/TestOutputSize-stderr.txt

@@ -1,2 +0,0 @@
-^Cannot find file: .*/Tests/RunCMake/CTestCommandLine/TestOutputSize/DartConfiguration.tcl
-Errors while running CTest

Tests/RunCMake/CTestCommandLine/TestOutputTruncation_head-stderr.txt

@@ -1 +0,0 @@
-^Cannot find file: .*/Tests/RunCMake/CTestCommandLine/TestOutputTruncation.*/DartConfiguration.tcl

Tests/RunCMake/CTestCommandLine/TestOutputTruncation_middle-stderr.txt

@@ -1 +0,0 @@
-^Cannot find file: .*/Tests/RunCMake/CTestCommandLine/TestOutputTruncation.*/DartConfiguration.tcl

Tests/RunCMake/CTestCommandLine/TestOutputTruncation_tail-stderr.txt

@@ -1 +0,0 @@
-^Cannot find file: .*/Tests/RunCMake/CTestCommandLine/TestOutputTruncation.*/DartConfiguration.tcl