Refactor timeline macro for compatibility with Jinja2 templates

[SriHV]

What is the context of this PR?

3171 ...

BREAKING CHANGE

We have made a breaking change to the timeline macro by renaming the items parameter to timelineItems. This change affects all instances where the timeline macro is used. Below, we provide detailed instructions on how to update your service to accommodate this change.

How to Update Your Code To update your service, you need to replace the items parameter with timelineItems wherever the timeline macro is used. Here is an example of how to make this change:

Before: {{ onsTimeline({ "items": [. . . ] }) }}

After: {{ onsTimeline({ "timelineItems": [. . . ] }) }}

How to review this PR

• Test the changes in Design system
• Pull the latest PR (link) which is in review. Follow the updated readme.
• Update the macro and test it in Flask.

Checklist

This needs to be completed by the person raising the PR.

• [x] I have selected the correct Assignee
• [x] I have linked the correct Issue

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[SriHV]

I am not sure I understand what has been changed? Looks like a parameter name has been changed from items to items_timeline but I didn't see any .items() functions?

oh sorry I wasn't clear. Items is a reserved name mainly used as a built-in function for dictionary data structure. So when trying to iterate over this parameter named 'items', we get this error 'builtin_function_or_method' object is not iterable.

[rmccar]

I am not sure I understand what has been changed? Looks like a parameter name has been changed from items to items_timeline but I didn't see any .items() functions?

oh sorry I wasn't clear. Items is a reserved name mainly used as a built-in function for dictionary data structure. So when trying to iterate over this parameter named 'items', we get this error 'builtin_function_or_method' object is not iterable.

Can this information be put into the description

[rmccar]

Can we have a "breaking changes" section added to the description that tells the user how to update their service to fix the breaking change we have introduced