Prepare release 3.0b0

pyproject.toml

 [tool.poetry]
 name = "AlekSIS-App-Untis"
-version = "3.0.dev0"
+version = "3.0.1.dev0"
 packages = [
     { include = "aleksis" }
 ]
@@ -41,8 +41,8 @@ python = "^3.9"
 mysqlclient = "^2.0.0"
 tqdm = "^4.44.1"
 defusedxml = "^0.7.0"
-aleksis-core = "^3.0.dev3"
-aleksis-app-chronos = "^3.0.dev1"
+aleksis-core = "^3.0"
+aleksis-app-chronos = "^3.0"
 
 [tool.poetry.dev-dependencies]
 aleksis-builddeps = "*"