Update storage provider StoreExisting method to take absolute file paths

storage/storage.go

@@ -34,7 +34,7 @@ func (sp FileSystemStorageProvider) StoreRaw(bucketName string, objectName strin
 }
 
 func (sp FileSystemStorageProvider) StoreExisting(bucketName string, objectName string, existingFilePath string) (string, error) {
-	bytesRead, err := afero.ReadFile(sp.fileSystem, existingFilePath)
+	bytesRead, err := os.ReadFile(existingFilePath)
 	if err != nil {
 		return "", err
 	}

storage/storage_test.go

@@ -33,7 +33,8 @@ func TestFileSystemStorageProvider(t *testing.T) {
 	t.Run("storeExisting method stores files in filesystem", func(t *testing.T) {
 		fileSystem := afero.NewMemMapFs()
 
-		afero.WriteFile(fileSystem, "/tmp/existing.bin", dummyData, os.ModePerm)
+		err := os.WriteFile("/tmp/existing.bin", dummyData, os.ModePerm)
+		assert.Nil(t, err)
 
 		provider := FileSystemStorageProvider{
 			fileSystem: fileSystem,