Update language to comply with inclusive guidance

Update android_app_set to use word install rather than master for
android_app_sets, this better matches the phrasing used for apex_set.

See https://source.android.com/setup/contribute/respectful-code for
reference

Bug: 161896447
Test: m nothing
Change-Id: I429e7f8b16c42c10ad4d9543110f5ce814a893b1
diff --git a/apex/androidmk.go b/apex/androidmk.go
index 82a902b..8a0c298 100644
--- a/apex/androidmk.go
+++ b/apex/androidmk.go
@@ -209,7 +209,7 @@
 			if !ok {
 				panic(fmt.Sprintf("Expected %s to be AndroidAppSet", fi.module))
 			}
-			fmt.Fprintln(w, "LOCAL_APK_SET_MASTER_FILE :=", as.MasterFile())
+			fmt.Fprintln(w, "LOCAL_APK_SET_INSTALL_FILE :=", as.InstallFile())
 			fmt.Fprintln(w, "LOCAL_APKCERTS_FILE :=", as.APKCertsFile().String())
 			fmt.Fprintln(w, "include $(BUILD_SYSTEM)/soong_android_app_set.mk")
 		case nativeSharedLib, nativeExecutable, nativeTest: