Update for pytest coverage regular expression

Hello. Here is my humble proposition for a modification of the recommended regular expression for capturing pytest coverage report, since the number of columns might depends:

^TOTAL\s+(?:\d+\s+){1,3,4}(\d+\%)$

Mine has 5 columns for example:

----------- coverage: platform linux, python 3.7.2-final-0 -----------
Name                                                 Stmts   Miss Branch BrPart  Cover
--------------------------------------------------------------------------------------
...
--------------------------------------------------------------------------------------
TOTAL                                                 1357    134    403     50    88%