g.extension: fix registration addon with module name start with 2 chars db.*, ps.*, r3.*, wx.*

[tmszi]

Describe the bug
Not all addon module are registered during installation on the OS MS Windows platform.

To Reproduce
Steps to reproduce the behavior:

1. Apply PR g.extension: fix installing addons on the OS MS Windows #3166 first please
2. Try install one of the addons which name start with two characters *db.*, ps.*, r3.*, wx.* e.g. g.extension db.join
3. Check if installed addon module is registered g.extension -a

Expected behavior
Addon module whose name start with two characters *db.*, ps.*, r3.*, wx.* should be registered during installation same as others addon module.

C:\Users\User>g.extension db.join
Downloading precompiled GRASS Addons <db.join>...
Fetching <db.join> from
<http://wingrass.fsv.cvut.cz/grass84/addons/grass-8.4.0dev/db.join.zip> (be
patient)...
Updating extension modules metadata file...
Installation of <db.join> successfully finished

C:\Users\User>g.extension -a
List of installed extensions (modules):
db.join

System description:

• Operating System: MS Windows
• GRASS GIS version: all

C:\Users\User>python3 -c "import sys, wx; print(sys.version); print(wx.version())
3.9.5 (tags/v3.9.5:0a7dcbd, May  3 2021, 17:27:52) [MSC v.1928 64 bit (AMD64)]
4.2.0 msw (phoenix) wxWidgets 3.2.1

Additional context
Problematic is regular expression which not catch addon module name which start with two character *db.*, ps.*, r3.*, wx.*.

grass/scripts/g.extension/g.extension.py

Lines 1635 to 1636 in 6ffd18f

	# Filter GRASS module name patterns
	if re.search(r"^[d,db,g,i,m,p,ps,r,r3,s,t,v,wx]\..*[\.py,\.exe]$", file):

Expected behavior:

In [1]: import re

In [2]: re.search(r"^([d,g,i,m,p,r,s,t,v]|^db|^ps|^r3|^wx)\..*[\.py,\.exe]$", "db.join.py")
Out[2]: <re.Match object; span=(0, 10), match='db.join.py'>