docs: consistently indent .rst files with 2 spaces

2 spaces is the most common indentation width used in the docs; adjust
the rest for consistency.

Also change .editorconfig accordingly.

.editorconfig

@@ -25,7 +25,7 @@ indent_size = 4
 
 [*.rst]
 indent_style = space
-indent_size = 3
+indent_size = 2
 
 [*.yml]
 indent_style = space

docs/dev/packages.rst

@@ -9,10 +9,13 @@ Development workflow
 When you are developing packages, it often happens that you iteratively want to deploy
 and verify the state your development. There are two ways to verify your changes:
 
-1) One way is to rebuild the complete firmware, flash it, configure it and verify your
+1)
+  One way is to rebuild the complete firmware, flash it, configure it and verify your
   development then. This usually takes at least a few minutes to get your changes
   working so you can test them. Especially if you iterate a lot, this becomes tedious.
-2) Another way is to rebuild only the package you are currently working on and
+
+2)
+  Another way is to rebuild only the package you are currently working on and
   to deploy this package to your test system. Here not even a reboot is required.
   This makes iterating relatively fast. Your test system could be real hardware or
   even a qemu in most cases.