[build, devscripts] Add devscript to set a build variant

Closes #4471

devscripts/make_readme.py

@@ -45,6 +45,10 @@ def apply_patch(text, patch):
 delim = f'\n{" " * switch_col_width}'
 
 PATCHES = (
+    (   # Standardize update message
+        r'(?m)^(    -U, --update\s+).+(\n    \s.+)*$',
+        r'\1Update this program to the latest version',
+    ),
     (  # Headings
         r'(?m)^  (\w.+\n)(    (?=\w))?',
         r'## \1'