Add german translation repo link (#42)

docs: add german translation

Author: mheob

README.md

@@ -2895,6 +2895,7 @@ This is also available in other languages:
   - [beginor/clean-code-typescript](https://github.com/beginor/clean-code-typescript)
   - [pipiliang/clean-code-typescript](https://github.com/pipiliang/clean-code-typescript)
 - ![fr](https://raw.githubusercontent.com/gosquared/flags/master/flags/flags/shiny/24/France.png) **French**: [ralflorent/clean-code-typescript](https://github.com/ralflorent/clean-code-typescript)
+- ![de](https://raw.githubusercontent.com/gosquared/flags/master/flags/flags/shiny/24/Germany.png) **German**: [mheob/clean-code-typescript](https://github.com/mheob/clean-code-typescript)
 - ![ja](https://raw.githubusercontent.com/gosquared/flags/master/flags/flags/shiny/24/Japan.png) **Japanese**: [MSakamaki/clean-code-typescript](https://github.com/MSakamaki/clean-code-typescript)
 - ![ko](https://raw.githubusercontent.com/gosquared/flags/master/flags/flags/shiny/24/South-Korea.png) **Korean**: [738/clean-code-typescript](https://github.com/738/clean-code-typescript)
 - ![ru](https://raw.githubusercontent.com/gosquared/flags/master/flags/flags/shiny/24/Russia.png) **Russian**: [Real001/clean-code-typescript](https://github.com/Real001/clean-code-typescript)