details: remove conversation color from appbar

New design don't include the conversation color in the appbar anymore.

GitLab: #1723
Change-Id: I06dbd75e9bef5063ed5f14cfcbd3321a2c2cad85

jami-android/app/src/main/java/cx/ring/client/ContactDetailsActivity.kt

@@ -235,14 +235,6 @@ class ContactDetailsActivity : AppCompatActivity(), ContactPickerFragment.OnCont
 
         binding.back.setOnClickListener { onBackPressedDispatcher.onBackPressed() }
         binding.addMember.setOnClickListener { ContactPickerFragment(conversation.contacts).show(supportFragmentManager, ContactPickerFragment.TAG) }
-
-        // Update color on RX color signal.
-        mDisposableBag.add(conversation.getColor()
-            .observeOn(DeviceUtils.uiScheduler)
-            .subscribe {
-                binding.appBar.backgroundTintList = ColorStateList.valueOf(getConversationColor(this, it))
-            }
-        )
     }
 
     private fun profileImageClicked() {