[docs] Correct wrong tracing transport option

[Tsuribori]

Description

The Advanced docs section on Tracing shows a wrong option relating to tracing transport security, the actual option is tracing-insecure-transport instead of tracing-insecure.

gotosocial/internal/config/config.go

Line 141 in 138cbe4

TracingInsecureTransport bool `name:"tracing-insecure-transport" usage:"Disable TLS for the gRPC or HTTP transport protocol"`

Checklist

• I/we have read the GoToSocial contribution guidelines.
• I/we have discussed the proposed changes already, either in an issue on the repository, or in the Matrix chat.
• I/we have performed a self-review of added code.
• I/we have written code that is legible and maintainable by others.
• I/we have commented the added code, particularly in hard-to-understand areas.
• I/we have made any necessary changes to documentation.
• I/we have added tests that cover new code.
• I/we have run tests and they pass locally with the changes.
• I/we have run go fmt ./... and golangci-lint run.

[daenney]

🤦 thank you, we missed that one in #2184.