Remove `//+build` tags, as the code does not compile on older versions of Go anymore

cmd/signaler_unix.go

@@ -1,5 +1,4 @@
 //go:build !windows && !plan9
-// +build !windows,!plan9
 
 package cmd
 

cmd/wire_injectors.go

@@ -1,5 +1,4 @@
 //go:build wireinject
-// +build wireinject
 
 package cmd
 

scanner/metadata/taglib/get_filename.go

@@ -1,5 +1,4 @@
 //go:build !windows
-// +build !windows
 
 package taglib
 

scanner/metadata/taglib/get_filename_win.go

@@ -1,5 +1,4 @@
 //go:build windows
-// +build windows
 
 package taglib
 

server/subsonic/responses/responses_test.go

@@ -1,5 +1,4 @@
 //go:build linux || darwin
-// +build linux darwin
 
 // TODO Fix snapshot tests in Windows
 // Response Snapshot tests. Only run in Linux and macOS, as they fail in Windows

server/subsonic/wire_injectors.go

@@ -1,5 +1,4 @@
 //go:build wireinject
-// +build wireinject
 
 package subsonic
 

tools.go

@@ -1,5 +1,4 @@
 //go:build tools
-// +build tools
 
 package main