Move git command to git/gitcmd (#35483)

The name cmd is already used in many places and may cause conflicts, so
I chose `gitcmd` instead to minimize potential naming conflicts.

modules/git/attribute/batch.go

@@ -12,6 +12,7 @@ import (
 	"time"
 
 	"code.gitea.io/gitea/modules/git"
+	"code.gitea.io/gitea/modules/git/gitcmd"
 	"code.gitea.io/gitea/modules/log"
 )
 
@@ -23,7 +24,7 @@ type BatchChecker struct {
 	stdOut        *nulSeparatedAttributeWriter
 	ctx           context.Context
 	cancel        context.CancelFunc
-	cmd           *git.Command
+	cmd           *gitcmd.Command
 }
 
 // NewBatchChecker creates a check attribute reader for the current repository and provided commit ID
@@ -76,7 +77,7 @@ func NewBatchChecker(repo *git.Repository, treeish string, attributes []string)
 			_ = lw.Close()
 		}()
 		stdErr := new(bytes.Buffer)
-		err := cmd.Run(ctx, &git.RunOpts{
+		err := cmd.Run(ctx, &gitcmd.RunOpts{
 			Env:    envs,
 			Dir:    repo.Path,
 			Stdin:  stdinReader,