Minor Improvements to the Shelly Gen3 docs (#1302)

* fix knowledge base url for Shelly 2 PM Gen3

* reference pinout image of Shelly 1 Mini Gen3 in the 1PM Mini Gen3 docs

Author: thiesgerken

src/docs/devices/Shelly-1PM-Mini-Gen3/index.md

@@ -22,6 +22,8 @@ Generation 3 of Shelly Mini. With Powermeter, and Relay
 
 The UART Pinout is the same as other Shelly Plus Mini.
 
+![Shelly 1 Mini Gen3](../Shelly-1-Mini-Gen3/shelly_1_mini_gen3_pcb_a.png "Shelly 1 Mini Gen3")
+
 ## GPIO Pinout
 
 | Pin    | Function  |

src/docs/devices/Shelly-2-PM-Gen3/index.md

@@ -11,7 +11,7 @@ difficulty: 2
 Generation 3 of Shelly 2. With Powermeter. \
 Generation 3 configurations are not compatible with earlier Shelly 2 generation hardware. \
 General hardware info, including serial pinout is on the
-[Shelly Knowledgebase](https://kb.shelly.cloud/knowledge-base/shelly-plus-2pm).
+[Shelly Knowledgebase](https://kb.shelly.cloud/knowledge-base/shelly-2pm-gen3).
 
 ## GPIO Pinout