change(jira-sync-actions): add deprecation info and warning message

sync_issues_to_jira/README.md

@@ -1,3 +1,7 @@
+:warning: **Deprecation Notice**: This GitHub action is deprecated and development will not continue here. We recommend migrating to the latest version available in the [espressif/sync-jira-actions](https://github.com/espressif/sync-jira-actions) project.
+
+---
+
 # GitHub to JIRA Issue Sync
 
 This is a GitHub action that performs simple one way syncing of GitHub issues into JIRA.

sync_issues_to_jira/sync_to_jira.py

@@ -14,6 +14,14 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 #
+import warnings
+warnings.simplefilter('default', DeprecationWarning)
+warnings.warn(
+    "You are using a deprecated version of the Jira sync GitHub action. "
+    "We recommend migrating to the latest version available at https://github.com/espressif/sync-jira-actions.",
+    DeprecationWarning
+)
+
 from jira import JIRA
 from github import Github
 import os
@@ -23,6 +31,7 @@
 from sync_issue import *
 
 
+
 class _JIRA(JIRA):
     def applicationlinks(self):
         return []  # disable this function as we don't need it and it makes add_remote_links() slow