security fix (osmdroid#1356)

prevent mitm codeinjection

see https://medium.com/@jonathan.leitschuh/want-to-take-over-the-java-ecosystem-all-you-need-is-a-mitm-1fc329d898fb

Author: k3b

build.gradle

@@ -40,7 +40,7 @@ allprojects {
         mavenCentral()
         mavenLocal()
         maven { url "https://oss.sonatype.org/content/repositories/snapshots" }
-        maven { url "http://repo.maven.apache.org/maven2" }
+        maven { url "https://repo.maven.apache.org/maven2" }
         maven {
             url 'https://maven.google.com/'
             name 'Google'