set background color for primary action buttons on upload and participate

Signed-off-by: Andy Scherzinger <info@andy-scherzinger.de>

src/main/java/com/owncloud/android/ui/activity/CommunityActivity.java

@@ -93,7 +93,7 @@ public class CommunityActivity extends FileActivity {
                                 getString(R.string.contributing_link)))));
 
         MaterialButton reportButton = findViewById(R.id.community_testing_report);
-        reportButton.getBackground().setColorFilter(ThemeUtils.primaryColor(this, true), PorterDuff.Mode.SRC_ATOP);
+        reportButton.setBackgroundColor(ThemeUtils.primaryColor(this,true));
         reportButton.setOnClickListener(v -> DisplayUtils.startLinkIntent(this, R.string.report_issue_link));
     }
 

src/main/java/com/owncloud/android/ui/activity/UploadFilesActivity.java

@@ -178,7 +178,7 @@ public class UploadFilesActivity extends FileActivity implements
         mCancelButton.setOnClickListener(this);
 
         mUploadBtn = findViewById(R.id.upload_files_btn_upload);
-        mUploadBtn.getBackground().setColorFilter(ThemeUtils.primaryColor(this, true), PorterDuff.Mode.SRC_ATOP);
+        mUploadBtn.setBackgroundColor(ThemeUtils.primaryColor(this,true));
         mUploadBtn.setOnClickListener(this);
 
         int localBehaviour = preferences.getUploaderBehaviour();