Update minimum documentation version to 2.6 [skip ci]

Author: halx99

.github/workflows/build.yml

@@ -19,13 +19,13 @@ on:
     inputs:
       min_doc_ver:
         # actions run ID
-        description: 'Please min doc version to build, example: 2.5'
+        description: 'Please min doc version to build, example: 2.6'
         # Default value if no value is explicitly provided
-        default: '2.5'
+        default: '2.6'
         # Input has to be provided for the workflow to run
         required: true
 env:
-  DEFAULT_MIN_DOC_VER: '2.5'
+  DEFAULT_MIN_DOC_VER: '2.6'
 jobs:
   build:
     runs-on: ubuntu-latest