core: Commonize close() between EuiccChannel's

app/src/main/java/im/angry/openeuicc/core/EuiccChannel.kt

@@ -32,5 +32,5 @@ abstract class EuiccChannel(
             return true
         }
 
-    abstract fun close()
+    fun close() = lpa.close()
 }

app/src/main/java/im/angry/openeuicc/core/OmapiApduInterface.kt

@@ -55,6 +55,4 @@ class OmapiChannel(
     override val lpa: LocalProfileAssistant = LocalProfileAssistantImpl(
         OmapiApduInterface(service, info),
         HttpInterfaceImpl())
-
-    override fun close() = lpa.close()
 }

app/src/main/java/im/angry/openeuicc/core/TelephonyManagerApduInterface.kt

@@ -60,6 +60,4 @@ class TelephonyManagerChannel(
         TelephonyManagerApduInterface(info, tm),
         HttpInterfaceImpl()
     )
-
-    override fun close() = lpa.close()
 }