Remove duplicate bindings

Some of these were defined in the shared bindings, some (like \cy yank)
were just literally duplicate in the same files.

This should _not_ change anything. In particular this does not remove
hardcoding of sequences (because terminfo might be wrong or the term
might need smkx).

Found with

```
function bind
	set -l binds (builtin bind)
    builtin bind $argv
    set -l newbinds (builtin bind)
    if set -q argv[1]; and not test "$argv[1]" = "--erase"
        if test "$binds" = "$newbinds"
            echo "Duplicate: " (string escape -- $argv)
        end
    end
end
```

share/functions/__fish_shared_key_bindings.fish

@@ -20,9 +20,6 @@ function __fish_shared_key_bindings -d "Bindings shared between emacs and vi mod
     bind $argv \cv fish_clipboard_paste
 
     bind $argv \e cancel
-    bind $argv \cy yank
-    bind $argv \ey yank-pop
-
     bind $argv \t complete
     # shift-tab does a tab complete followed by a search.
     bind $argv --key btab complete-and-search

share/functions/fish_default_key_bindings.fish

@@ -71,9 +71,6 @@ function fish_default_key_bindings -d "Default (Emacs-like) key bindings for fis
 	bind \ed forward-kill-word
 	bind \ed kill-word
 
-	# escape cancels stuff	
-	bind \e cancel
-
 	# Ignore some known-bad control sequences
 	# https://github.com/fish-shell/fish-shell/issues/1917
 	bind \e\[I 'begin;end'

share/functions/fish_vi_key_bindings.fish

@@ -80,13 +80,6 @@ function fish_vi_key_bindings --description 'vi-like key bindings for fish'
 
     bind k up-or-search
     bind j down-or-search
-    bind \e\[A up-or-search
-    bind \e\[B down-or-search
-    bind -k down down-or-search
-    bind -k up up-or-search
-    bind \eOA up-or-search
-    bind \eOB down-or-search
-
     bind b backward-word
     bind B backward-bigword
     bind ge backward-word