pix: replace logo with SVG (#382)

Source: https://onelessthing.co.uk/resources/downloads/One-Less-Thing-Domestic-Cleaning-Client-Handbook.pdf

Minimized.

_sponsors.html

@@ -114,7 +114,7 @@
 <div class="silver"><p> <a class="x" href="https://iboysoft.com" rel="sponsored"><img src="pix/silver/iBoysoft.svg" alt="iBoysoft"></a></div>
 <div class="silver"><p> <a class="x" href="https://www.testarna.se/casino/utan-svensk-licens" rel="sponsored"><img src="pix/silver/testarna.png" alt="Testarna"></a></div>
 <div class="silver"><p> <a class="x" href="https://fineproxy.org/" rel="sponsored"><img src="pix/silver/fineproxy.jpg" alt="Fineproxy"></a></div>
-<div class="silver"><p> <a class="x" href="https://onelessthing.co.uk/" rel="sponsored"><img src="pix/silver/onelessthing.png" alt="Onelessthing"></a></div>
+<div class="silver"><p> <a class="x" href="https://onelessthing.co.uk/" rel="sponsored"><img src="pix/silver/onelessthing.svg" alt="Onelessthing"></a></div>
 <div class="silver"><p> <a class="x" href="https://bountii.coupons/" rel="sponsored"><img src="pix/silver/bountii.png" alt="Bountii"></a></div>
 <div class="silver"><p> <a class="x" href="https://proxy.coupons" rel="sponsored"><img src="pix/silver/proxycoupons.png" alt="Proxycoupons"></a></div>
 <div class="silver"><p> <a class="x" href="https://earthweb.com/" rel="sponsored"><img src="pix/silver/earthweb.png" alt="Earthweb"></a></div>

mk-sponsors.pl

@@ -23,7 +23,7 @@
     'https://bountii.coupons/' => 'bountii.png',
     'https://earthweb.com/' => 'earthweb.png',
     'https://proxy.coupons' => 'proxycoupons.png',
-    'https://onelessthing.co.uk/' => 'onelessthing.png',
+    'https://onelessthing.co.uk/' => 'onelessthing.svg',
 
     # Sponsors that don't get images
     'babiel-gmbh' => '[none]',  # special case handled in _sponsors.html