doc(): fix typo and broken link

[dancer1325]

Description

• Fix typo and broken link

Context

• Navigate to https://grafana.com/docs/pyroscope/latest/view-and-analyze-profile-data/flamegraphs/ and check
  

How to review?

• Check link refer to an existing document and it's properly closed

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[dancer1325]

Maybe @knylander-grafana ?

[dancer1325]

Label: type/docs