Fix typos in PSLE certificate explanatory notes

[elliotwutingfeng]

Before

Candidates will be awarded one og the following grades:

After

Candidates will be awarded one of the following grades:

---

name: Certificate Template Addition
about: This is the workflow for requesting new certificate templates to be added to
the OpenCerts repository
title: "[New Template]"
labels: new template
assignees: ''

---

Pull Request Guidelines for Adding Certificate Templates

This document is a work in progress but here are some basic checks. As these are only basic guidelines, meeting the below doesn't indicate there will be no issues with your pull request.

Pre-merge checks

• Did not modify any files outside of your organisation's template folder (e.g package-lock.json or anything else)
• Ensure that your code has been rebased on top of latest OpenCerts master
• Linter issues resolved (Run npm run lint:fix to see issues)
• npm run test passes
• npm run test:integration passes
• Travis Build passes

Certificate Template

• No more than 5 templates or 25 added/modified files in the pull request
• Ensure that your .opencert file's data complies with the intentions of the OpenCerts' schema - e.g recipient related information is inside the recipient object, etc.
• Integration test for each template that checks that the correct rendering is done given a sample certificate
• Sample certificate file included for each template, located alongside the integration test for each template
• Sample certificates must obviously be a sample certificate
  • Obviously fictitious name
  • Obviously sample signatory images
• No fixed-size raster images as part of certificate layout
• Mobile responsive design
• Date parsing should be localised to template author's timezone
• Webpack chunking code is correct
  • Has chunking code
  • Same chunking code as the other certificates belonging to that institute
• Certificate Store Addresses have been updated
  • Template Whitelist
  • Registry
• Template should not be using resources(images etc.) on the website outside of their own folder (e.g institute logo shouldn't be used from /static because there's no guarantee it will not change)