speech: fix the mixed indentation in godoc
speech: fix the mixed indentation in godoc

Change-Id: I22fe423b9e0ff508bd027338be510ea1533332d6
Reviewed-on: https://code-review.googlesource.com/7712
Reviewed-by: Jonathan Amsterdam <e3d3698b2ccd5955e4adf250d0785062d0f9018b@google.com>

googleapis/google-cloud-go,michael-grosshans/google-cloud-go,googleapis/google-cloud-go,googleapis/google-cloud-go,michael-grosshans/google-cloud-go,googleapis/google-cloud-go