Changed Installation notes in the README.md file, since ModiaBase is now registered

Author: MartinOtter

README.md

@@ -39,11 +39,10 @@ but can also be utilized in another context. Especially the following functional
 
 ## Installation
 
-The package is currently being registered. During this phase, it is installed as
-(Julia >= 1.5 is required):
+The package is registered and is installed with (Julia >= 1.5 is required):
 
 ```julia
-julia> ]add https://github.com/ModiaSim/ModiaBase.jl#main
+julia> ]add ModiaBase
 ```
 
 It is recommended to also add the following packages, in order that all tests and examples can be executed in an own environment (`]test ModiaBase` works without adding these packages).