feat: use hashed uses string as cache dir name (#186)

Port of https://gitea.com/gitea/act/pulls/117

Refs forgejo/act#100

Co-authored-by: Jason Song <i@wolfogre.com>
Reviewed-on: https://code.forgejo.org/forgejo/act/pulls/186
Reviewed-by: Michael Kriese <michael.kriese@gmx.de>

act/model/workflow.go

@@ -1,9 +1,12 @@
 package model
 
 import (
+	"crypto/sha256"
+	"encoding/hex"
 	"errors"
 	"fmt"
 	"io"
+	"path/filepath"
 	"reflect"
 	"regexp"
 	"strconv"
@@ -734,6 +737,12 @@ func (s *Step) Type() StepType {
 	return StepTypeUsesActionRemote
 }
 
+func (s *Step) UsesHash() string {
+	hashBytes := sha256.Sum256([]byte(s.Uses))
+	hashString := hex.EncodeToString(hashBytes[:])
+	return filepath.Join(hashString[:2], hashString[2:])
+}
+
 // ReadWorkflow returns a list of jobs for a given workflow file reader
 func ReadWorkflow(in io.Reader, validate bool) (*Workflow, error) {
 	if validate {