avoid test variant error output
avoid test variant error output

If no variant is present, the diff script used to output a line like

numdiff: <bla>/tests/trilinos/precondition_muelu_q_iso_q1.with_trilinos>=11.14.with_64bit_indices=off.output.*: No such file or directory

because a glob in a for statement in bash will return it literally if no
files matches the pattern. This fixes it.

danshapero/dealii,ibkim11/dealii,gpitton/dealii,angelrca/dealii,maieneuro/dealii,nicolacavallini/dealii,nicolacavallini/dealii,maieneuro/dealii,spco/dealii,andreamola/dealii,angelrca/dealii,naliboff/dealii,shakirbsm/dealii,andreamola/dealii,jperryhouts/dealii,shakirbsm/dealii,kalj/dealii,jperryhouts/dealii,angelrca/dealii,naliboff/dealii,JaeryunYim/dealii,nicolacavallini/dealii,adamkosik/dealii,shakirbsm/dealii,ESeNonFossiIo/dealii,pesser/dealii,gpitton/dealii,jperryhouts/dealii,pesser/dealii,EGP-CIG-REU/dealii,naliboff/dealii,JaeryunYim/dealii,spco/dealii,EGP-CIG-REU/dealii,Arezou-gh/dealii,kalj/dealii,EGP-CIG-REU/dealii,JaeryunYim/dealii,sairajat/dealii,naliboff/dealii,adamkosik/dealii,adamkosik/dealii,Arezou-gh/dealii,Arezou-gh/dealii,JaeryunYim/dealii,JaeryunYim/dealii,kalj/dealii,gpitton/dealii,EGP-CIG-REU/dealii,andreamola/dealii,naliboff/dealii,angelrca/dealii,naliboff/dealii,gpitton/dealii,sairajat/dealii,adamkosik/dealii,Arezou-gh/dealii,shakirbsm/dealii,danshapero/dealii,spco/dealii,maieneuro/dealii,jperryhouts/dealii,ibkim11/dealii,EGP-CIG-REU/dealii,Arezou-gh/dealii,sairajat/dealii,maieneuro/dealii,ibkim11/dealii,maieneuro/dealii,ESeNonFossiIo/dealii,shakirbsm/dealii,pesser/dealii,andreamola/dealii,adamkosik/dealii,shakirbsm/dealii,sairajat/dealii,kalj/dealii,danshapero/dealii,adamkosik/dealii,angelrca/dealii,ESeNonFossiIo/dealii,ESeNonFossiIo/dealii,gpitton/dealii,sairajat/dealii,sairajat/dealii,pesser/dealii,spco/dealii,maieneuro/dealii,ibkim11/dealii,spco/dealii,kalj/dealii,Arezou-gh/dealii,ESeNonFossiIo/dealii,danshapero/dealii,andreamola/dealii,jperryhouts/dealii,sairajat/dealii,ibkim11/dealii,danshapero/dealii,angelrca/dealii,pesser/dealii,gpitton/dealii,JaeryunYim/dealii,danshapero/dealii,andreamola/dealii,EGP-CIG-REU/dealii,ibkim11/dealii,jperryhouts/dealii,spco/dealii,adamkosik/dealii,EGP-CIG-REU/dealii,ibkim11/dealii,danshapero/dealii,nicolacavallini/dealii,angelrca/dealii,nicolacavallini/dealii,gpitton/dealii,andreamola/dealii,naliboff/dealii,shakirbsm/dealii,nicolacavallini/dealii,ESeNonFossiIo/dealii,pesser/dealii,JaeryunYim/dealii,nicolacavallini/dealii,ESeNonFossiIo/dealii,spco/dealii,Arezou-gh/dealii,pesser/dealii,maieneuro/dealii,kalj/dealii,jperryhouts/dealii,kalj/dealii