[7.x] renames SIEM to Security Solution (#70070)

[MadameSheema]

Backports the following commits to 7.x:

• renames SIEM to Security Solution ([SIEM] Renames SIEM to Security Solution for cyclic dependency test message #70070)

[kibanamachine]

💚 Build Succeeded

• continuous-integration/kibana-ci/pull-request
• Commit: c0a168c

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