changed submit button label

we create a "task" not a "post"...
minor #4364 changed submit button label (OskarStark)

This PR was submitted for the 2.5 branch but it was merged into the 2.3 branch instead (closes #4364).

Discussion
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changed submit button label

we create a "task" not a "post"...

Commits
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d3ea36c changed submit button label