Updating Focus Friday section of Sales Handbook to reflect new pilot timeframe

Why is this change being made?

Updating Focus Friday timeline to reflect new, extended pilot timeframe. Reference: https://gitlab.slack.com/archives/C0259241C/p1599688537192200

Author Checklist

• Provided a concise title for the MR
• Added a description to this MR explaining the reasons for the proposed change, per [say-why-not-just-what][transparency]
• Assign this change to the correct DRI
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  • If the changes relate to any part of the project other than updates to content and/or data files please make sure to ping @gl-static-site-editor in a comment for a review and merge. For example changes to .gitlab-ci.yml, JavaScript/CSS/Ruby code or the layout files.