Update docs/developer/package-integration/flux.md,...

Package Merge Request

Package Changes

Minor grammar/formatting/punctuation edits made to multiple Package Integration pages, including: Flux, Helm Standards, Istio Hardening, and Monitoring.

Package MR

(Link to Package MR here)

For Issue

Closes (link to issue here)

Upgrade Notices

(Include any relevant notes about upgrades here or write "N/A" if there are none)