updated Bengali translation, activated in credits

This introduces a new string for the translation!

changelog.md

@@ -8,7 +8,7 @@
  ### Packaging
  ### Terrain
  ### Translations
-   * Updated translations: German
+   * Updated translations: Bengali, German
  ### Units
  ### User interface
  ### WML Engine

data/core/about_i18n.cfg

@@ -61,12 +61,17 @@ sort=yes
     [/entry]
 [/about]
 
-# no strings committed so far
-#[about]
-#    title = _"Bengali Translation" # wmllint: no spellcheck
-#    #    [entry]
-#    #    [/entry]
-#[/about]
+[about]
+    title = _"Bengali Translation" # wmllint: no spellcheck
+    [entry]
+        name = "Subhraman Sarkar (LumiousE/babaissarkar)"
+        email = "suvrax_AT_gmail_DOT_com"
+    [/entry]
+    [entry]
+        name = "Tahsin J Khalid (Lord-Knightmare)"
+        comment = "current maintainer"
+    [/entry]
+[/about]
 
 [about]
     title = _"Bulgarian Translation" # wmllint: no spellcheck