Connects to #361. PASS1B-06 metabolomics DEA search result updates.

[jimmyzhen]

Key Changes:

• For PASS1B-06 metabolite DEA results search, the metabolite field used for retrieving data has now been changed to metabolite_refmet due to re-indexing metabolite DEA results using meta-regression datasets.
• Added new UI on homepage for users to subscribe to future data updates.
• Updated homepage UIs towards the end of the page due to the newly added subscription UI.
• Updated homepage CSS to handle viewport responsiveness due to the newly added subscription UI.
• Added styling to visually emphasize the first 2 PreCAWG onboarding bullet points.
• Changed dependencies to improve page load time for pages with embedded YouTube videos.

[jyu-sm]

checked the metabolomics data search and the subscription link. They look good.

[cteng585]

Mostly looks good to me. My one piece of feedback is that the "module" prior to the office hours/signup "module" doesn't indicate that the user can scroll further down to see the office hours signups/data release subscription.

Also, I feel like the wording here can be workshopped:

Deep dive into our source codes integral to the MoTrPAC 6 month old rats performing endurance training exercise study, from ingestion to QC and from processing to analysis.

Specifically, "...into our source codes integral..." reads awkwardly to me.

[jimmyzhen]

@cteng585 thank you for the comments. How would you change the wording for the code repo section?