chore: bump SDK_VERSION to 5.4.1

NOTE: This makes 5.4.1 the same as 5.1.38.
* Maven Central doesn't allow unpublishing a version.
A future 5.4.2 release will be made on top of the 5.4.0 base after all
issues have been addressed and tested.

Author: jkasten2

Examples/OneSignalDemo/gradle.properties

@@ -17,4 +17,4 @@ android.enableJetifier=false
 
 # This is the name of the SDK to use when building your project.
 # This will be fed from the GitHub Actions workflow.
-SDK_VERSION=5.1.38
+SDK_VERSION=5.4.1

OneSignalSDK/gradle.properties

@@ -33,4 +33,4 @@ android.useAndroidX = true
 
 # This is the name of the SDK to use when building your project.
 # This will be fed from the GitHub Actions workflow.
-SDK_VERSION=5.1.38
+SDK_VERSION=5.4.1