Secret Site Properties added, formatting, typo

[sebastian-krempel]

• Added paragraph on new Is secure property for Site Properties since LifeTime 11.20.1, Platform Server 11.25.0, and Service Studio 11.54.35.
• Formatted UI elements to be bold according to style guide.
• Fixed number of "default maximum records" in the text to match with value 10 used in the steps below.

[outsystemsbot]

Hello @sebastian-krempel 👋

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[sebastian-krempel]

I read, understood and accept the OutSystems CLA