Update log collector docs for the fluentd to fluent-bit migration (EV-6164) - #2815

[vale] reported by reviewdog 🐶 [Vale.Spelling] Did you really mean 'Unparseable'? Raw Output: {"message":"[Vale.Spelling] Did you really mean 'Unparseable'?","location":{"path":"calico-enterprise/release-notes/index.mdx","range":{"start":{"line":72,"column":234},"end":{"line":72,"column":245}}},"severity":"ERROR","code":{"value":"Vale.Spelling"}}

[vale] reported by reviewdog 🐶 [Vale.Terms] Use 'ConfigMap' instead of 'configmap'. Raw Output: {"message":"[Vale.Terms] Use 'ConfigMap' instead of 'configmap'.","location":{"path":"calico-enterprise/release-notes/index.mdx","range":{"start":{"line":26,"column":134},"end":{"line":26,"column":143}}},"severity":"WARNING","code":{"value":"Vale.Terms"}}

[vale] reported by reviewdog 🐶 [Vale.Terms] Use 'DaemonSet' instead of 'daemonset'. Raw Output: {"message":"[Vale.Terms] Use 'DaemonSet' instead of 'daemonset'.","location":{"path":"calico-enterprise/observability/elastic/dns/filtering-dns.mdx","range":{"start":{"line":28,"column":21},"end":{"line":28,"column":30}}},"severity":"WARNING","code":{"value":"Vale.Terms"}}