[BOT-X] Improve weather warnings, including Telegram message refactor

[miguelcarreiro]

Description

This pull request refactors Telegram warning messages, and fixes some bugs.

Task items:

• [x] Refactor Telegram warning messages (including a new image, and a different message from Discord and Twitter);
• [x] Fix >280 character tweet bug;
• [x] Fix Telegram API rate limit error;
• [x] Define different Discord channels for mainland, Madeira and Azores warnings.

Requirements

Requirements when deploying the current work to an environment (dev, staging or production):

• Add WARNINGS_AZ_CHANNEL_ID and WARNINGS_MD_CHANNEL_ID variables in .env file.

[coveralls]

Pull Request Test Coverage Report for Build 630

• 16 of 77 (20.78%) changed or added relevant lines in 4 files are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage decreased (-1.3%) to 56.422%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/services/Telegram.js	6	17	35.29%
src/services/Warnings.js	6	56	10.71%
<!--	Total:	16	77	20.78%	-->

Files with Coverage Reduction	New Missed Lines	%
src/services/Warnings.js	1	14.63%
<!--	Total:	1		-->

Totals
Change from base Build 628:	-1.3%
Covered Lines:	494
Relevant Lines:	828

---

💛 - Coveralls