vine manual spelling errors

[btovar]

Proposed Changes

Give an overall description of the changes, along with the context and motivation.
Mention relevant issues and pull requests as needed.

Merge Checklist

The following items must be completed before PRs can be merged.
Check these off to verify you have completed all steps.

• make test Run local tests prior to pushing.
• make format Format source code to comply with lint policies. Note that some lint errors can only be resolved manually (e.g., Python)
• make lint Run lint on source code prior to pushing.
• Manual Update: Update the manual to reflect user-visible changes.
• Type Labels: Select a github label for the type: bugfix, enhancement, etc.
• Product Labels: Select a github label for the product: TaskVine, Makeflow, etc.
• PR RTM: Mark your PR as ready to merge.