refactor(util): reuse timer handles in Debouncer

lua/git.lua

@@ -1,4 +1,3 @@
-local log = require("log")
 local util = require("util")
 
 local HIGHLIGHTS = {
@@ -97,21 +96,13 @@ local Repo = {}
 Repo.__index = Repo
 
 function Repo:start_watcher()
-    local watcher, err_msg, err_name = vim.uv.new_fs_event()
-    if not watcher then
-        log.error(
-            "Failed to create fs event watcher: %s (%s)",
-            err_msg,
-            err_name
-        )
-        return
-    end
-    watcher:start(self.gitdir, {}, function(err, filename)
+    local watcher = assert(vim.uv.new_fs_event())
+    assert(watcher:start(self.gitdir, {}, function(err, filename)
         if err or (filename ~= "index" and filename ~= "HEAD") then
             return
         end
         self.refresh:call()
-    end)
+    end))
     self.watcher = watcher
 end