DOCS-3038: Document BGPPeer connectionMode for Calico Enterprise 3.23.3 - #3158

[vale] reported by reviewdog 🐶 [Vale.Spelling] 'connectionMode' looks like code; format it as code. Raw Output: {"message":"[Vale.Spelling] 'connectionMode' looks like code; format it as code.","location":{"path":"calico-enterprise_versioned_docs/version-3.23-2/reference/resources/bgppeer.mdx","range":{"start":{"line":66,"column":3},"end":{"line":66,"column":17}}},"severity":"ERROR","code":{"value":"Vale.Spelling"}}

[vale] reported by reviewdog 🐶 [Vale.Spelling] Did you really mean 'reconvergence'? Raw Output: {"message":"[Vale.Spelling] Did you really mean 'reconvergence'?","location":{"path":"calico-enterprise_versioned_docs/version-3.23-2/networking/configuring/bgp-to-workload.mdx","range":{"start":{"line":268,"column":18},"end":{"line":268,"column":31}}},"severity":"ERROR","code":{"value":"Vale.Spelling"}}