Fix mailto://ip.addr support

[caronc]

Description:

Related issue (if applicable): #1113

This was broken in #1095 where the mailto:// syntax got a bit smarter and made mailto:// syntax shorter for most cases. However it broke the mailto://ip.address references ( 👀 )

This PR resolves this issue.

Checklist

• The code change is tested and works locally.
• There is no commented out code in this PR.
• No lint errors (use flake8)
• 100% test coverage

Testing

Anyone can help test this source code as follows:

# Create a virtual environment to work in as follows:
python3 -m venv apprise

# Change into our new directory
cd apprise

# Activate our virtual environment
source bin/activate

# Install the branch
pip install git+https://github.com/caronc/apprise.git@1113-mailto-ipaddr-fix

# Test out the changes with the following command:
apprise -t "Test Title" -b "Test Message" \
  "mailto://1.2.3.4"

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 99.27%. Comparing base (22c979d) to head (37230de).

❗ Your organization needs to install the Codecov GitHub app to enable full functionality.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #1114   +/-   ##
=======================================
  Coverage   99.27%   99.27%           
=======================================
  Files         139      139           
  Lines       18053    18055    +2     
  Branches     3688     3689    +1     
=======================================
+ Hits        17923    17925    +2     
  Misses        121      121           
  Partials        9        9           

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.