Only check and config git on web subcommand but not others (#7236)

* only check and config git on web subcommand but not others

* add Init in git tests

modules/git/git_test.go

@@ -0,0 +1,25 @@
+// Copyright 2019 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package git
+
+import (
+	"fmt"
+	"os"
+	"testing"
+)
+
+func fatalTestError(fmtStr string, args ...interface{}) {
+	fmt.Fprintf(os.Stderr, fmtStr, args...)
+	os.Exit(1)
+}
+
+func TestMain(m *testing.M) {
+	if err := Init(); err != nil {
+		fatalTestError("Init failed: %v", err)
+	}
+
+	exitStatus := m.Run()
+	os.Exit(exitStatus)
+}