keymap: Update Prev to Previous follow-up (#25931)

Follow-up for https://github.com/zed-industries/zed/pull/25909

Add three more action replacements:

```
1. "pane::ActivatePrevItem" -> "pane::ActivatePreviousItem"
2. "vim::MoveToPrev" -> "vim::MoveToPrevious"
3. "vim:MoveToPrevMatch" -> "vim:MoveToPreviousMatch" 
```

Release Notes:

- N/A

assets/keymaps/linux/jetbrains.json

@@ -2,7 +2,7 @@
   {
     "bindings": {
       "ctrl-alt-s": "zed::OpenSettings",
-      "ctrl-{": "pane::ActivatePrevItem",
+      "ctrl-{": "pane::ActivatePreviousItem",
       "ctrl-}": "pane::ActivateNextItem"
     }
   },

assets/keymaps/linux/sublime_text.json

@@ -1,9 +1,9 @@
 [
   {
     "bindings": {
-      "ctrl-{": "pane::ActivatePrevItem",
+      "ctrl-{": "pane::ActivatePreviousItem",
       "ctrl-}": "pane::ActivateNextItem",
-      "ctrl-pageup": "pane::ActivatePrevItem",
+      "ctrl-pageup": "pane::ActivatePreviousItem",
       "ctrl-pagedown": "pane::ActivateNextItem",
       "ctrl-1": ["workspace::ActivatePane", 0],
       "ctrl-2": ["workspace::ActivatePane", 1],