chore: Drop embedmd in favor of gomplate

[mrueg]

What this PR does / why we need it:
We can use gomplate for templating here as well, which removes the need to install an additional tool every time.

How does this change affect the cardinality of KSM: (increases, decreases or does not change cardinality)
None
Which issue(s) this PR fixes: (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged)
Fixes #

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