Remove manifest.scm as moved on to docker based testing

manifest.scm

@@ -1,25 +0,0 @@
-;; What follows is a "manifest" equivalent to the command line you gave.
-;; You can store it in a file that you may then pass to any 'guix' command
-;; that accepts a '--manifest' (or '-m') option.
-
-(specifications->manifest
-  (list
-    ; Guile
-    "guile"
-    ; Racket
-    "racket-minimal"
-    ; Gambit
-    "gambit-c"
-    ; Chicken
-    "chicken"
-    ; Gerbil
-    "gerbil"
-    ; Cyclone
-    "ck"
-    ; Kawa
-    "openjdk"
-    ; Test libraries
-    "curl"
-    ; Compilers
-    "zig"
-    "gcc-toolchain"))