docs: `ecosystem/integrations` update 2 (#5282)
# docs: ecosystem/integrations update 2
#5219 - part 1
The second part of this update (parts are independent of each other! no
overlap):
- added diffbot.md
- updated confluence.ipynb; added confluence.md
- updated college_confidential.md
- updated openai.md
- added blackboard.md
- added bilibili.md
- added azure_blob_storage.md
- added azlyrics.md
- added aws_s3.md
## Who can review?
@hwchase17@agola11
@agola11
@vowelparrot
@dev2049
