docs: Update Linux build prerequisites (#1208)

* docs: Update Linux build prerequisites

* docs: Remove `python -m pip install mako` from CONTRIBUTING.md

Author: bkeryan

CONTRIBUTING.md

@@ -77,7 +77,9 @@ For Debian/Ubuntu, install git, cmake (3.18.0 or newer), and mako:
 > sudo apt-get update
 > sudo apt-get install git
 > sudo apt-get install cmake
-> python -m pip install mako
+> sudo apt-get install g++
+> sudo apt-get install python3-venv  # for ensurepip
+> sudo apt-get install ninja-build   # optional
 ```
 
 For NI Linux RT, install packagegroup-core-buildessential, git, git-perltools, cmake (3.18.0 or newer), python3-utils, and mako: