Switch to use -f instead of -F for sendmail

[zeripath]

It appears that the sendmail function has been incorrect from its merging. We should use -f not -F.

From http://man7.org/linux/man-pages/man8/sendmail.8.html

      -F full_name
              Set  the  sender  full name. This overrides the NAME environment
              variable, and is used only with messages that have no From: mes-
              sage header.

       -f sender
              Set  the  envelope  sender  address.  This  is the address where
              delivery problems are sent to. With Postfix versions before 2.1,
              the   Errors-To:  message  header  overrides  the  error  return
              address.

Fix #9385

[guillep2k]

It's weird, this have been working fine since #355! How is this possible?

[codecov-io]

Codecov Report

Merging #9961 into master will decrease coverage by <.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #9961      +/-   ##
==========================================
- Coverage   42.24%   42.24%   -0.01%     
==========================================
  Files         610      610              
  Lines       80274    80274              
==========================================
- Hits        33914    33912       -2     
- Misses      42198    42199       +1     
- Partials     4162     4163       +1

Impacted Files	Coverage Δ
modules/process/manager.go	74.69% <0%> (-3.62%)	⬇️
models/repo.go	49.69% <0%> (-0.14%)	⬇️
services/pull/patch.go	67.92% <0%> (ø)	⬆️
services/pull/temp_repo.go	34.18% <0%> (+2.56%)	⬆️

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[zeripath]

I suspect it has not been working fine!

[6543]

I think this can be easely backported to 1.10.x too

[zeripath]

Make lg-tm work

[6543]

pleace send backport