Update voters.rst

Corrected the service name to be injected0
bug #4165 Update voters.rst (gerryvdm)

This PR was submitted for the 2.5 branch but it was merged into the 2.4 branch instead (closes #4165).

Discussion
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Update voters.rst

Corrected the service name to be injected

Commits
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f0a46c9 Update voters.rst