Bump org.webjars:bootstrap from 4.0.0-beta to 4.0.0-beta.2

Bumps [org.webjars:bootstrap](https://github.com/webjars/bootstrap) from 4.0.0-beta to 4.0.0-beta.2.
- [Commits](webjars/bootstrap@bootstrap-4.0.0-beta...bootstrap-4.0.0-beta.2)

---
updated-dependencies:
- dependency-name: org.webjars:bootstrap
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

build.gradle

@@ -69,7 +69,7 @@ dependencies {
     implementation 'com.google.zxing:core:3.5.0'
     implementation 'com.google.zxing:javase:3.5.0'
 
-    implementation 'org.webjars:bootstrap:4.0.0-beta'
+    implementation 'org.webjars:bootstrap:4.0.0-beta.2'
     implementation 'org.webjars.bower:eonasdan-bootstrap-datetimepicker:4.17.37'
     implementation 'org.webjars.bower:momentjs:2.10.6'
     implementation 'org.webjars.bowergithub.wisvch:bootstrap-theme:4.6.1-3'