Test examples/step-36: do not compare test output

Step 36 computes a spectrum with slepc containing eigenvalues with
multiplicities. Unfortunately, it is up to chance (i.e., slepc version,
compiler and cpu) which multiplicities it prints and how many iterations
it needs for that. Thus disable comparing the test output.

diff --git a/tests/examples/step-36.mpirun=1.with_petsc=true.with_slepc=true.output b/tests/examples/step-36.mpirun=1.with_petsc=true.with_slepc=true.run_only
similarity index 100%
rename from tests/examples/step-36.mpirun=1.with_petsc=true.with_slepc=true.output
rename to tests/examples/step-36.mpirun=1.with_petsc=true.with_slepc=true.run_only