Minor fix on Markdown to follow markdown rules

[NargiT]

• https://github.com/DavidAnson/markdownlint/blob/v0.13.0/doc/Rules.md#md007
• https://github.com/DavidAnson/markdownlint/blob/v0.13.0/doc/Rules.md#md004
• https://github.com/DavidAnson/markdownlint/blob/v0.13.0/doc/Rules.md#md034
• http -> https
• add alt to the demo gif

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Error creating deployment, please see controller logs for details.

[priyawadhwa]

LGTM, thanks for your contribution!