Update reference to keymap.json in tasks docs (zed-industries#11711)

I assume this was an older file name or just a typo as I can't find any
other references to a `keybindings.json` file. Either way it was
confusing for a bit :)

Release Notes:

- N/A

docs/src/tasks.md

@@ -73,7 +73,7 @@ The intended use of ephemeral tasks is to stay in the flow with continuous `task
 
 ## Custom keybindings for tasks
 
-You can define your own keybindings for your tasks via additional argument to `task::Spawn`. If you wanted to bind the aforementioned `echo current file's path` task to `alt-g`, you would add the following snippet in your `keybindings.json` file:
+You can define your own keybindings for your tasks via additional argument to `task::Spawn`. If you wanted to bind the aforementioned `echo current file's path` task to `alt-g`, you would add the following snippet in your [`keymap.json`](./key-bindings/) file:
 
 ```json
 {