Remove redundant variable dedeclarations

In go 1.22, loop variables are redeclared with each iteration of the
loop, rather than simple updated on each iteration. This means that we
no longer need to manually redeclare variables when they're closed over
by a function.

pkg/commands/git_commands/commit_loader.go

@@ -505,8 +505,6 @@ func (self *CommitLoader) getExistingMainBranches() []string {
 
 	for i, branchName := range mainBranches {
 		wg.Add(1)
-		i := i
-		branchName := branchName
 		go utils.Safe(func() {
 			defer wg.Done()