Remove references to Jobs in examples in Grammar and mechanics guide

[marijnschraagen]

Is your feature request related to a problem? Please describe.
The Grammar and mechanics guide (https://stackoverflow.design/content/guidelines/grammar-and-mechanics) contains several references to the Jobs product. This product has been discontinued (https://meta.stackoverflow.com/questions/415293/sunsetting-jobs-developer-story/).

Examples:

Buttons and links: Post job
Feature or product names: job alerts
Colons: Your job listing was published on January 15
Exclamation points: You’ve published your first job listing!

Describe the solution you'd like
The examples should be updated in order to either reference still existing products or not reference any product at all.