build: switch to Gradle's maven-publish plugin

Signed-off-by: Harsh Shandilya <me@msfjarvis.dev>

build.gradle

@@ -4,7 +4,6 @@ buildscript {
         agpVersion = '4.1.0'
         annotationsVersion = '1.1.0'
         appcompatVersion = '1.2.0'
-        bintrayPluginVersion = '1.8.5'
         biometricVersion = '1.1.0-beta01'
         collectionVersion = '1.1.0'
         constraintLayoutVersion = '2.0.2'
@@ -19,7 +18,6 @@ buildscript {
         kotlinVersion = '1.4.10'
         lifecycleRuntimeKtxVersion = '2.3.0-alpha07'
         materialComponentsVersion = '1.3.0-alpha03'
-        mavenPluginVersion = '2.1'
         preferenceVersion = '1.1.1'
         zxingEmbeddedVersion = '3.6.0'
 
@@ -28,8 +26,6 @@ buildscript {
     dependencies {
         classpath "com.android.tools.build:gradle:$agpVersion"
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlinVersion"
-        classpath "com.github.dcendents:android-maven-gradle-plugin:$mavenPluginVersion"
-        classpath "com.jfrog.bintray.gradle:gradle-bintray-plugin:$bintrayPluginVersion"
     }
     repositories {
         google()