Bump mockito-core from 3.0.0 to 3.1.0

Bumps [mockito-core](https://github.com/mockito/mockito) from 3.0.0 to 3.1.0.
- [Release notes](https://github.com/mockito/mockito/releases)
- [Commits](mockito/mockito@v3.0.0...v3.1.0)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Author: dependabot-preview[bot]

browserup-proxy-core/build.gradle

@@ -90,7 +90,7 @@ dependencies {
     testImplementation 'org.hamcrest:hamcrest:2.1'    
     testImplementation 'org.hamcrest:hamcrest-library:2.1'
     testImplementation 'com.github.tomakehurst:wiremock-jre8:2.24.1'
-    testImplementation 'org.mockito:mockito-core:3.0.0'
+    testImplementation 'org.mockito:mockito-core:3.1.0'
     testImplementation 'org.seleniumhq.selenium:selenium-firefox-driver:3.141.59'
     testImplementation 'org.apache.httpcomponents:httpclient:4.5.10'
 }

browserup-proxy-mitm/build.gradle

@@ -80,5 +80,5 @@ dependencies {
     testImplementation 'org.codehaus.groovy:groovy-all:2.5.8'
     testImplementation 'org.hamcrest:hamcrest:2.1'
     testImplementation 'org.hamcrest:hamcrest-library:2.1'
-    testImplementation 'org.mockito:mockito-core:3.0.0'
+    testImplementation 'org.mockito:mockito-core:3.1.0'
 }

browserup-proxy-rest/build.gradle

@@ -97,7 +97,7 @@ dependencies {
     testImplementation 'org.codehaus.groovy.modules.http-builder:http-builder:0.7.2'
     testImplementation 'org.hamcrest:hamcrest:2.1'
     testImplementation 'org.hamcrest:hamcrest-library:2.1'
-    testImplementation 'org.mockito:mockito-core:3.0.0'
+    testImplementation 'org.mockito:mockito-core:3.1.0'
     testImplementation 'org.seleniumhq.selenium:selenium-api:3.4.0'
     testImplementation 'org.awaitility:awaitility:4.0.1'
     testImplementation 'xyz.rogfam:littleproxy:2.0.0-beta-3'