Install docs - Remove .NET 7 where it makes sense

[adegeo]

Summary

• Remove .NET 7.0 from supported tables\lists.
• Other minor changes.
• Update some metadata descriptions.

Fixes #40772

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📄 File	🔗 Preview link
docs/core/install/linux-alpine.md	Install the .NET SDK or the .NET Runtime on Alpine
docs/core/install/linux-centos.md	Install .NET on CentOS Linux
docs/core/install/linux-debian.md	Install the .NET SDK or the .NET Runtime on Debian
docs/core/install/linux-fedora.md	docs/core/install/linux-fedora
docs/core/install/linux-opensuse.md	Install the .NET SDK or the .NET Runtime on openSUSE
docs/core/install/linux-rhel.md	Install .NET on RHEL and CentOS Stream
docs/core/install/linux-scripted-manual.md	Install .NET on Linux by using an install script or by extracting binaries
docs/core/install/linux-sles.md	docs/core/install/linux-sles
docs/core/install/linux-ubuntu-install.md	Install .NET SDK or .NET Runtime on Ubuntu
docs/core/install/linux-ubuntu.md	Get OS version info
docs/core/install/macos.md	Install .NET on macOS
docs/core/install/remove-runtime-sdk-versions.md	How to remove the .NET Runtime and SDK
docs/core/install/templates.md	Manage .NET project and item templates
docs/core/install/upgrade.md	docs/core/install/upgrade
docs/core/install/windows.md	Install .NET on Windows

[BillWagner]

Once the build errors are addressed, this is ready to merge.