Fix links

[adriendupuis]

Question	Answer
JIRA Ticket	N/A
Versions	master, 4.6
Edition	N/A

Few broken links found while reviewing #2627

INFO    -  Doc file 'multisite/languages/automated_translations.md' contains an unrecognized relative link 'ai_actions_md', it was left as is.
INFO    -  Doc file 'multisite/languages/automated_translations.md' contains a link '##add-a-custom-field-encoder', but there is no such anchor on this page.
INFO    -  Doc file 'pim/attributes/date_and_time.md' contains a link '../products.md#attributes', but the doc 'pim/products.md' does not contain an anchor '#attributes'.
INFO    -  Doc file 'pim/attributes/date_and_time.md' contains a link '../../content_management/data_migration/importing_data.md#date-and-time-attribute', but the doc
           'content_management/data_migration/importing_data.md' does not contain an anchor '#date-and-time-attribute'.

Checklist

• Text renders correctly
• Text has been checked with vale
• Description metadata is up to date
• Redirects cover removed/moved pages
• Code samples are working
• PHP code samples have been fixed with PHP CS fixer
• Added link to this PR in relevant JIRA ticket or code PR

[github-actions]

Preview of modified Markdown:

• docs/multisite/languages/automated_translations.md
• docs/pim/attributes/date_and_time.md