Bump libphonenumber from 8.12.27 to 8.12.28

Bumps [libphonenumber](https://github.com/google/libphonenumber) from 8.12.27 to 8.12.28.
- [Release notes](https://github.com/google/libphonenumber/releases)
- [Changelog](https://github.com/google/libphonenumber/blob/master/making-metadata-changes.md)
- [Commits](https://github.com/google/libphonenumber/compare/v8.12.27...v8.12.28)

---
updated-dependencies:
- dependency-name: com.googlecode.libphonenumber:libphonenumber
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

matrix-sdk-android/build.gradle

@@ -169,7 +169,7 @@ dependencies {
     implementation 'com.otaliastudios:transcoder:0.10.3'
 
     // Phone number https://github.com/google/libphonenumber
-    implementation 'com.googlecode.libphonenumber:libphonenumber:8.12.27'
+    implementation 'com.googlecode.libphonenumber:libphonenumber:8.12.28'
 
     testImplementation 'junit:junit:4.13.2'
     testImplementation 'org.robolectric:robolectric:4.5.1'

vector/build.gradle

@@ -360,7 +360,7 @@ dependencies {
     implementation 'com.facebook.stetho:stetho:1.6.0'
 
     // Phone number https://github.com/google/libphonenumber
-    implementation 'com.googlecode.libphonenumber:libphonenumber:8.12.27'
+    implementation 'com.googlecode.libphonenumber:libphonenumber:8.12.28'
 
     // rx
     implementation 'io.reactivex.rxjava2:rxkotlin:2.4.0'