[integrations] - Improve docs & fix minor bugs for Microsoft exchange online message trace

[ShourieG]

Type of change

• Bug

Proposed commit message

1. Improved documentation so now it redirects users to the recently updated official Microsoft docs.
2. Updated the default value of scope as the existing value was wrong.
3. Updated the default value for login url by removing a trailing / which could cause errors in authentication, if not updated by the user.

Checklist

• I have reviewed tips for building integrations and this pull request is aligned with them.
• I have verified that all data streams collect metrics or logs.
• I have added an entry to my package's changelog.yml file.
• I have verified that Kibana version constraints are current according to guidelines.

Author's Checklist

• [ ]

How to test this PR locally

Related issues

• Relates [Microsoft Exchange Online Message Trace] Improve docs for OAuth2 support #7658

Screenshots

[elasticmachine]

Pinging @elastic/security-external-integrations (Team:Security-External Integrations)

[elasticmachine]

💚 Build Succeeded

the below badges are clickable and redirect to their specific view in the CI or DOCS

Expand to view the summary

Build stats

• Start Time: 2023-10-12T10:16:36.286+0000

• Duration: 24 min 23 sec

Test stats 🧪

Test	Results
Failed	0
Passed	7
Skipped	0
Total	7

🤖 GitHub comments

Expand to view the GitHub comments

To re-run your PR in the CI, just comment with:

• /test : Re-trigger the build.

[elasticmachine]

🌐 Coverage report

Name	Metrics % (covered/total)	Diff
Packages	100.0% (1/1)	💚
Files	100.0% (1/1)	💚
Classes	100.0% (1/1)	💚
Methods	100.0% (15/15)	💚
Lines	98.106% (259/264)	❕
Conditionals	100.0% (0/0)	💚

[kgeller]

LGTM

[elasticmachine]

Package microsoft_exchange_online_message_trace - 1.13.1 containing this change is available at https://epr.elastic.co/search?package=microsoft_exchange_online_message_trace