Render caret names in resolve testData, so that we don't have to guess
the indices of the carets;
it makes the multi-caret testData less error-prone.
Relevant for KT-65152 and KT-62695
Allow multiple carets to be used in reference resolve tests.
Adjust the testdata for the only test case which has actually
had multiple carets in it.
Required for KT-65152 and KT-62695