pages*: improve list placeholders and wording of descriptions (#12111)

* pages*: improve wording and list placeholders

* clamav: fix verb tenses

Co-authored-by: Juri Dispan <juri.dispan@posteo.net>

* buzzphrase: use k instead of n for number of phrases

Co-authored-by: Juri Dispan <juri.dispan@posteo.net>

* adguardhome: use non-default instead of different

* adguardhome: use configuration instead of config

Co-authored-by: K.B.Dharun Krishna <kbdharunkrishna@gmail.com>

* goimports, module: fix list placeholders

Co-authored-by: K.B.Dharun Krishna <kbdharunkrishna@gmail.com>

* pages*: leave stems and extensions in the same placeholders

* pages*: fix list placeholders

* pages*: fix list placeholders

* pages*: apply suggestions from code review

Co-authored-by: Lena <126529524+acuteenvy@users.noreply.github.com>

* qpdf: enclose n with backticks

Co-authored-by: Lena <126529524+acuteenvy@users.noreply.github.com>

---------

Co-authored-by: Juri Dispan <juri.dispan@posteo.net>
Co-authored-by: K.B.Dharun Krishna <kbdharunkrishna@gmail.com>
Co-authored-by: Lena <126529524+acuteenvy@users.noreply.github.com>

pages/common/ffmpeg.md

@@ -5,7 +5,7 @@
 
 - Extract the sound from a video and save it as MP3:
 
-`ffmpeg -i {{path/to/video.mp4}} -vn {{path/to/sound}}.mp3`
+`ffmpeg -i {{path/to/video.mp4}} -vn {{path/to/sound.mp3}}`
 
 - Save a video as GIF, scaling the height to 1000px and setting framerate to 15: