inspiral_intrinsics.py: correct error formatting

This small change corrects string formatting in error messages in inspiral_intrinsics.py

assigned to @cort.posnansky

added 2 commits

• 17623ea8 - 1 commit from branch master
• 0818d216 - inspiral_intrinsics.py: correct error formatting

Compare with previous version

enabled an automatic merge when the pipeline for 0818d216 succeeds

merged