Update the license_expression and spdx_license_expression to SingleLineField from StringField

Signed-off-by: Chin Yeung Li <[email protected]>

Author: chinyeungli

src/attributecode/model.py

@@ -798,12 +798,12 @@ def set_standard_fields(self):
             ('package_url', PackageUrlField()),
             ('notes', StringField()),
 
-            ('license_expression', StringField()),
+            ('license_expression', SingleLineField()),
             ('license_key', ListField()),
             ('license_name', ListField()),
             ('license_file', FileTextField()),
             ('license_url', UrlListField()),
-            ('spdx_license_expression', StringField()),
+            ('spdx_license_expression', SingleLineField()),
             ('spdx_license_key', ListField()),
             ('copyright', StringField()),
             ('notice_file', FileTextField()),