typing: simplify archive.gz writing and drop a few pytype suppressions
I was waiting until 3.8 to use `Literal` to fix this, but there's also the ":"
and "|" characters that are passed along here, meant only for the non-gz archive
types. But manipulating what the local caller passes is silly- we know we're
writing, so just open it for writing. As an added bonus, PyCharm stops flagging
the call too (since it doesn't know about pytype suppression comments).
$ hg init repo
$ cd repo
$ touch a
$ unset HGUSER
$ echo "[ui]" >> .hg/hgrc
$ echo "username= foo" >> .hg/hgrc
$ echo " bar1" >> .hg/hgrc
$ hg ci -Am m
adding a
abort: username 'foo\nbar1' contains a newline
[255]
$ rm .hg/hgrc
$ HGUSER=`(echo foo; echo bar2)` hg ci -Am m
adding a
abort: username 'foo\nbar2' contains a newline
[255]
$ hg ci -Am m -u "`(echo foo; echo bar3)`"
adding a
transaction abort!
rollback completed
abort: username 'foo\nbar3' contains a newline
[50]