2128 + service: Detect config file on service run correctly

Cose #2128

Squashed commit of the following:

commit cb7a582
Author: ArtemBaskal <a.baskal@adguard.com>
Date:   Thu Sep 24 21:03:43 2020 +0300

    2128 + service: Detect config file on service run correctly

home/home.go

@@ -147,13 +147,8 @@ func version() string {
 // run is a blocking method!
 // nolint
 func run(args options) {
-	// config file path can be overridden by command-line arguments:
-	if args.configFilename != "" {
-		Context.configFilename = args.configFilename
-	} else {
-		// Default config file name
-		Context.configFilename = "AdGuardHome.yaml"
-	}
+	// configure config filename
+	initConfigFilename(args)
 
 	// configure working dir and config path
 	initWorkingDir(args)
@@ -411,6 +406,16 @@ func writePIDFile(fn string) bool {
 	return true
 }
 
+func initConfigFilename(args options) {
+	// config file path can be overridden by command-line arguments:
+	if args.configFilename != "" {
+		Context.configFilename = args.configFilename
+	} else {
+		// Default config file name
+		Context.configFilename = "AdGuardHome.yaml"
+	}
+}
+
 // initWorkingDir initializes the workDir
 // if no command-line arguments specified, we use the directory where our binary file is located
 func initWorkingDir(args options) {

home/service.go

@@ -164,6 +164,8 @@ func handleServiceControlAction(opts options) {
 			log.Fatalf("Failed to run service: %s", err)
 		}
 	} else if action == "install" {
+		initConfigFilename(opts)
+		initWorkingDir(opts)
 		handleServiceInstallCommand(s)
 	} else if action == "uninstall" {
 		handleServiceUninstallCommand(s)