Integrated Alerting: `<` (less-than symbol) wrongly interpreted by Alert templates (as `&lt;`)

The symbol "<" in alert templates is converted to "&lt ;" in alert rules.
Other symbol ">" is processed correctly.

Build-in and custom alert templates are affected. 

STR:

• Add a new alert template with the symbol "<" in formula or use a built-in one (e.g. MySQL restarted)
  
• Use this template for an alert rule
• Check alert rule on the pmm server side (/etc/ia/rules)