Automation page thrown error 500 after installing Jira Service Management

Issue Summary

Automation page thrown error 500 after installing Jira Service Management

Steps to Reproduce

1. In a Jira Core or Jira Software instance install Automation for Jira plugin.
2. From Applications>Versions and Licenses also install the Jira Service Management obr.
3. Go to the project settings of any project in the instance and select Project Automation.
4. Observe that the page thrown an error 500:
   
5. Expand the Request Assistance button and observe following error:
   

   com.google.template.soy.tofu.SoyTofuException: In 'print' tag, expression "$localeString" evaluates to undefined.
   

In the atlassian-jira.log the following exception is thrown out:

ERROR   [c.a.j.web.servlet.InternalServerErrorServlet] {errorId=3ea31fed-08d8-4eb2-a6ad-512c33a922bc, interpretedMsg=, cause=com.google.template.soy.tofu.SoyTofuException: In 'print' tag, expression "$localeString" evaluates to undefined., stacktrace=com.google.template.soy.tofu.SoyTofuException: In 'print' tag, expression "$localeString" evaluates to undefined.
at JIRA.Automation.Project.Admin.Page.iframe(automation-admin-page.soy:53) [?:?]
2020-12-18 13:39:29,182+0000 automation-rule-executor:thread-5 ERROR tmarchionni   [c.c.a.api.service.ComponentChainImpl] Unexpected runtime error executing component for config 'ComponentConfigBean{id='121', component=TRIGGER, parentId='null', conditionParentId='null', schemaVersion=1, type='jira.jql.scheduled', value=JqlScheduledTriggerConfig{jql='status = 'in progress'', executionMode=jql, onlyUpdatedIssues=true, processIssuesInBulk=false}, conditions=[], children=[], optimisedIds=[]}': 
java.lang.NoClassDefFoundError: com/atlassian/servicedesk/api/ServiceDeskService
	at com.codebarrel

Expected Results

Automation for Jira plugin should continue to work as expected

Actual Results

Automation for Jira is not anymore operational

Workaround

Workaround 1

Restart the Jira application.

Workaround 2

From Administration > Manage Apps > Manage apps screen, manually disable and re-enable the Automation for Jira plugin.

Important Note: the 2nd workaround only works with Jira 8.x / Jira Service Management 4.x. It does not work on Jira 9.x / JSM 5.x. For such version, please use the 1st workaround.