fix: remove obsolete TeX instructions from README (#826)

Author: david-christiansen

README.md

@@ -49,35 +49,7 @@ up to date.
 
 ## Building the Reference Manual Locally
 
-This reference manual contains figures that are built from LaTeX
-sources. To build them, you'll need the following:
-
-- A LaTeX installation, including LuaLaTeX and the following packages
-  from TeXLive:
-    - `scheme-minimal`
-    - `latex-bin`
-    - `fontspec`
-    - `standalone`
-    - `pgf`
-    - `pdftexcmds`
-    - `luatex85`
-    - `lualatex-math`
-    - `infwarerr`
-    - `ltxcmds`
-    - `xcolor`
-    - `fontawesome`
-    - `spath3`
-    - `inter`
-    - `epstopdf-pkg`
-    - `tex-gyre`
-    - `tex-gyre-math`
-    - `unicode-math`
-    - `amsmath`
-    - `sourcecodepro`
-- `pdftocairo`, which can be found in the `poppler-utils` package on
-  Debian-derived systems and the `poppler` package in Homebrew
-
-Additionally, to run the style checker locally, you'll need
+To run the style checker locally, you'll need
 [Vale](https://vale.sh/). It runs in CI, so this is not a necessary
 step to contribute.