Explicitly set the escape parser directive on Windows

Author: MisterDA

src-opam/opam.ml

@@ -177,7 +177,7 @@ let from ?win10_revision ?arch ?maintainer ?img ?tag d =
 let header ?win10_revision ?arch ?maintainer ?img ?tag d =
   let parser_directives =
     match D.os_family_of_distro d with
-    | `Windows | `Cygwin -> parser_directive (`Escape '`')
+    | `Windows | `Cygwin -> empty
     | _ -> buildkit_syntax
   in
   parser_directives
@@ -448,7 +448,9 @@ let windows_mingw_opam2 ?win10_revision ?winget ?(labels = []) ?arch
     let extra, pkgs = Windows.Cygwin.ocaml_for_windows_packages ~extra () in
     Windows.Cygwin.install_cygwin ~msvs_tools:true ~extra () @@ pkgs
   in
-  winget_image @@ opams_image
+  parser_directive (`Escape '`')
+  @@ comment "Autogenerated by OCaml-Dockerfile scripts"
+  @@ winget_image @@ opams_image
   @@ header ?win10_revision ?arch distro
   @@ label (("distro_style", "windows") :: labels)
   @@ user "ContainerAdministrator"
@@ -493,7 +495,9 @@ let windows_msvc_opam2 ?win10_revision ?winget ?(labels = []) ~opam_hashes
     Windows.Cygwin.install_cygwin ~msvs_tools:true ~extra ()
     @@ vs_build_tools @@ pkgs
   in
-  winget_image @@ opams_image
+  parser_directive (`Escape '`')
+  @@ comment "Autogenerated by OCaml-Dockerfile scripts"
+  @@ winget_image @@ opams_image
   @@ header ?win10_revision ?arch distro
   @@ label (("distro_style", "windows") :: labels)
   @@ user "ContainerAdministrator"

src-opam/windows.ml

@@ -82,9 +82,7 @@ let header ~alias ?win10_revision
     ?(version =
       (Distro.win10_latest_image : Distro.win10_release :> Distro.win_all)) () =
   let img, tag = Distro.win10_base_tag ?win10_revision `Windows version in
-  parser_directive (`Escape '`')
-  @@ from ~alias ~tag img
-  @@ user "ContainerAdministrator"
+  from ~alias ~tag img @@ user "ContainerAdministrator"
 
 let sanitize_reg_path () =
   run