Add full path to images in PieSocket docs

[Tijani-Dia]

No description provided.

[Stormheg]

This is a known issue with mkdocs: mkdocs/mkdocs#1757

[codecov-commenter]

Codecov Report

Merging #98 (8ca6a71) into main (73b9ca1) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main      #98   +/-   ##
=======================================
  Coverage   98.27%   98.27%           
=======================================
  Files          30       30           
  Lines         927      927           
  Branches       87       87           
=======================================
  Hits          911      911           
  Misses         10       10           
  Partials        6        6           

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[Stormheg]

The issue over at mkdocs suggests setting site_url and using relative paths to images. I've added two commits to that effect.