Documentation does not render ending emoji Properly

[Sweetdevil144]

Remember to label the issue with the appropriate area, and also assign it to yourself if you plan to work on the issue in the near future.

Describe the bug

Documentation errors are as follow :

The like line of the Contributing to AzureTRE docs are rendered as follow : Thanks! :heart: :heart: :heart: when I visit it from my Brave and Safari browser.

Steps to reproduce

1. Visit the webpage at https://microsoft.github.io/AzureTRE/latest/contributing/
2. Navigate to the bottom of page at the end of How to Contribute to our Documentation section
3. Observe the last line

Azure TRE release version (e.g. v0.14.0 or main):

Deployed Azure TRE components - click the (i) in the UI:

[tim-allen-ck]

good spot.
It looks like there is a markdown extension missing from the mkdocs.yml

AzureTRE/mkdocs.yml

Lines 33 to 45 in 9d0bf31

	markdown_extensions:
	- pymdownx.superfences:
	custom_fences:
	- name: mermaid
	class: mermaid
	format: !!python/name:pymdownx.superfences.fence_code_format
	- meta
	- admonition
	- pymdownx.highlight
	- pymdownx.pathconverter
	- mdx_truly_sane_lists
	- pymdownx.tabbed
	- pymdownx.tasklist

for reference