Remove link to Crystal site

Author: oprypin

docs/assets/script.js

@@ -15,9 +15,6 @@ theme:
     primary: teal
     accent: purple
 
-extra_javascript:
-  - assets/script.js
-
 markdown_extensions:
   - pymdownx.highlight
   - pymdownx.magiclink
@@ -31,7 +28,6 @@ markdown_extensions:
       permalink: "#"
 
 nav:
-  - mkdocstrings-crystal: /mkdocstrings-crystal/
   - section-index: README.md
   - literate-nav: /mkdocs-literate-nav/
   - gen-files: /mkdocs-gen-files/