Downgrade kotlinx.coroutines to 0.26.1

Downgraded because of this bug in 0.27.0:
Kotlin/kotlinx.coroutines#626

Author: LouisCAD

build.gradle

@@ -55,7 +55,7 @@ allprojects {
         arch_room_version = '1.0.0'
         constraintLayout_version = '1.1.3'
         timber_version = '4.7.1'
-        kotlinxCoroutines_version = '0.27.0'
+        kotlinxCoroutines_version = '0.26.1'
     }
 }