Final call: explicit-svg-img, add <text> example

Hey folks,

This PR adds a failed example using <text> in an SVG element. This final
call lasts until October 12th. If you have any comments, please leave a
review:
https://github.com/act-rules/act-rules.github.io/pull/1467

-- 
*Wilco Fiers*
Axe-core product owner - Co-facilitator WCAG-ACT - Chair ACT-R


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