Update event template to accept an end date for multi-day events (not required)

Author: cthow83

.github/ISSUE_TEMPLATE/add-to-calendar.yml

@@ -1,13 +1,13 @@
 name: 💁🏽‍♀️ Add an event for maintainers to the calendar 🎙
 description: Use this form to add an event for maintainers or highlighting maintainers to the Maintainer Month calendar.
-title: "EVENT_NAME"
+title: 'EVENT_NAME'
 
 body:
   - type: markdown
     attributes:
       value: |
         :tada: Thanks for letting us know about an upcoming event! :tada:
-        
+
         Use this form to add an event for maintainers or highlighting maintainers to the Maintainer Month calendar. Your request will be reviewed within 72 hours.
 
   - id: eventname
@@ -16,36 +16,44 @@ body:
       label: Event Name
     validations:
       required: true
-      
+
   - id: date
     type: input
     attributes:
       label: Event Date
-      placeholder: "MM/DD"
+      placeholder: 'MM/DD'
     validations:
       required: true
 
+  - id: endDate
+    type: input
+    attributes:
+      label: Event End Date
+      placeholder: 'MM/DD'
+    validations:
+      required: false
+
   - id: UTCStartTime
     type: input
     attributes:
       label: Start time in UTC
-      placeholder: "14:00"
+      placeholder: '14:00'
     validations:
       required: true
 
   - id: UTCEndTime
     type: input
     attributes:
       label: End time in UTC
-      placeholder: "15:00"
+      placeholder: '15:00'
     validations:
       required: true
 
   - id: type
     type: dropdown
     attributes:
       label: Event Type
-      description: "Type of event"
+      description: 'Type of event'
       options:
         - conference
         - podcast
@@ -61,15 +69,15 @@ body:
     type: input
     attributes:
       label: Event Language
-      description: "Primary language of the event (e.g., English, Spanish, Mandarin)"
+      description: 'Primary language of the event (e.g., English, Spanish, Mandarin)'
     validations:
       required: true
 
   - id: location
     type: input
     attributes:
       label: Event Location
-      description: "Primary location of the event - either Virtual or a City + Country"
+      description: 'Primary location of the event - either Virtual or a City + Country'
     validations:
       required: true
 
@@ -85,25 +93,25 @@ body:
     type: input
     attributes:
       label: Event URL
-      description: "Web URL of event"
-      placeholder: "https://"
+      description: 'Web URL of event'
+      placeholder: 'https://'
 
   - id: eventdescription
     type: textarea
     attributes:
       label: Event Description
-      description: "What is this event about?"
-  
+      description: 'What is this event about?'
+
   - id: expectedparticipants
     type: input
     attributes:
       label: Participants
-      description: "Expected number of participants"
-      placeholder: "###"
-  
+      description: 'Expected number of participants'
+      placeholder: '###'
+
   - id: expectedmaintainers
     type: input
     attributes:
       label: Maintainers
-      description: "Expected number of maintainers participating"
-      placeholder: "###"
+      description: 'Expected number of maintainers participating'
+      placeholder: '###'