Bump version to 3.1.3

Signed-off-by: Michael Obi <[email protected]>

Author: michael-paystack

build.gradle

@@ -3,7 +3,7 @@
 buildscript {
     ext.kotlin_version = '1.3.72'
     repositories {
-        jcenter()
+        mavenCentral()
         google()
     }
     dependencies {
@@ -17,7 +17,6 @@ buildscript {
 
 allprojects {
     repositories {
-        jcenter()
         google()
         mavenCentral()
     }
@@ -27,8 +26,8 @@ ext {
     compileSdkVersion = 29
     minSdkVersion = 16
     targetSdkVersion = 29
-    versionCode = 18
+    versionCode = 19
 
     buildToolsVersion = "29.0.2"
-    versionName = "3.1.2"
+    versionName = "3.1.3"
 }