[Chapel Merge] Stop some chpldoc tests from leaving some tmp file

Branch: refs/heads/master
Revision: 8d800c9
Author: lydia-duncan
Log Message:

Merge pull request #17901 from lydia-duncan/cleanupTemps

Stop some chpldoc tests from leaving some tmp files around
[very minor, not reviewed]

Using -i for the sed command in the PREDIFF for these chpldoc test folders was
causing us to leave behind some *.tmp-e files in those directories. Stop using
-i so that these files are no longer generated.

It seems like these files were only left around on OSX, but the change does improve
the situation there and I noticed no negative effects on Linux

The impacted tests were run on OSX and Linux both before and after this change

Modified Files:
M test/chpldoc/compflags/folder/PREDIFF

M test/chpldoc/compflags/version/PREDIFF

Compare: https://github.com/chapel-lang/chapel/compare/866aedb8f62b...8d800c952782