add testing files and create create scan command

cli/testdata/expected/git/small-branch-foo.txt

@@ -0,0 +1,17 @@
+import (
+	"fmt"
+	"os"
+)
+	// seems safer
+	aws_token := os.Getenv("AWS_TOKEN")
+package foo
+
+import "fmt"
+
+func Foo() {
+	fmt.Println("foo")
+
+	// seems safe
+	aws_token := "AKIALALEMEL33243OLIA"
+	fmt.Println(aws_token)
+}

cli/testdata/expected/git/small.txt

@@ -0,0 +1,67 @@
+import (
+	"fmt"
+	"os"
+)
+	// seems safer
+	aws_token := os.Getenv("AWS_TOKEN")
+package foo
+
+import "fmt"
+
+func Foo() {
+	fmt.Println("foo")
+
+	// seems safe
+	aws_token := "AKIALALEMEL33243OLIA"
+	fmt.Println(aws_token)
+}
+package api
+
+import "fmt"
+
+func PrintHello() {
+	fmt.Println("hello")
+}
+import (
+	"fmt"
+	"os"
+)
+	var a = "initial"
+	fmt.Println(a)
+	var b, c int = 1, 2
+	fmt.Println(b, c)
+	var d = true
+	fmt.Println(d)
+	var e int
+	fmt.Println(e)
+	// load secret via env
+	awsToken := os.Getenv("AWS_TOKEN")
+
+	f := "apple"
+	fmt.Println(f)
+    
+    // opps I added a secret at line 20
+    awsToken := "AKIALALEMEL33243OLIA"
+package main
+
+import "fmt"
+
+func main() {
+
+    var a = "initial"
+    fmt.Println(a)
+
+    var b, c int = 1, 2
+    fmt.Println(b, c)
+
+    var d = true
+    fmt.Println(d)
+
+    var e int
+    fmt.Println(e)
+
+    f := "apple"
+    fmt.Println(f)
+}
+# test
+This is a repo used for testing gitleaks