Remove buildSrc module's dependency on JCenter

(cherry picked from commit 33660de6b1)

# Conflicts:
#	build.gradle.kts

app/build.gradle.kts

@@ -342,11 +342,6 @@ buildscript {
     }
 }
 
-repositories {
-    mavenCentral()
-    jcenter()
-}
-
 
 // Git is needed in your system PATH for these commands to work.
 // If it's not installed, you can return a random value as a workaround

build.gradle.kts

@@ -9,11 +9,9 @@ plugins {
 allprojects {
     repositories {
         mavenCentral()
-        jcenter()
         google()
         maven { setUrl("https://www.jitpack.io") }
-        maven { setUrl("https://oss.sonatype.org/content/repositories/snapshots/") }
-        maven { setUrl("https://dl.bintray.com/ibm-cloud-sdks/ibm-cloud-sdk-repo") }
+        jcenter()
     }
 }
 

buildSrc/build.gradle.kts

@@ -2,5 +2,5 @@ plugins {
     `kotlin-dsl`
 }
 repositories {
-    jcenter()
+    mavenCentral()
 }