[maint] update build docs for Fedora, doc non-obvious tex dep

Fedora was listed twice: consolodate.  texlive-scheme-basic does
not pull in `standalone.cls` which leads to nonobvious error messages.

readme/LinuxBuild.md

@@ -1,12 +1,14 @@
 # Xournal++ Linux Build
 
 ## Install dependencies
+
+Please create pull requests (or file issues) if you have more precise dependencies.
+
 ### For Fedora/CentOS/RHEL:
-````bash
-dnf groups install "C Development Tools and Libraries"
-dnf install cmake texlive-scheme-basic texlive-dvipng poppler-glib-devel portaudio-devel libsndfile-devel
-# AND SOME MORE please create Pull / write ticket if you have the exact dependencies
-````
+```bash
+sudo dnf install cmake gtk3-devel libxml2-devel cppunit-devel portaudio-devel libsndfile-devel \
+poppler-glib-devel texlive-scheme-basic texlive-dvipng 'tex(standalone.cls)' gettext
+```
 
 ### For Ubuntu/Debian:
 ````bash
@@ -21,11 +23,6 @@ texlive-dvipng texlive libxml2-devel \
 libpoppler-glib-devel
 ```
 
-### For Fedora:
-```bash
-sudo dnf install libxml2-devel cppunit-devel gtk3-devel cmake-gui portaudio-devel libsndfile-devel \
-texlive-scheme-basic texlive-dvipng poppler-glib-devel
-```
 
 ## Basic steps are:
 ````bash