Backport of fix(connect envoy): set initial_fetch_timeout to wait for initial xDS into release/1.14

[DanStough]

This is a manual backport of #17317 .

The below text is copied from the body of the original PR.

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Description

Consul updates for #17283.

This changes the time Envoy waits for the initial xDS configuration from the default (15s) to indefinitely. This prevents Envoy from starting with only a partial list of listeners/clusters.

Testing & Reproduction steps

Goldenfile tests have been updated since this affects Envoy's bootstrap configuration.

PR Checklist

• updated test coverage
• external facing docs updated
• appropriate backport labels added
• not a security concern

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[wilkermichael]

Just noting that the following files don't exist from https://github.com/hashicorp/consul/pull/17317/files
command/connect/envoy/testdata/access-logs-enabled-custom.golden
command/connect/envoy/testdata/access-logs-enabled.golden
command/connect/envoy/testdata/acl-enabled-and-token.golden
command/connect/envoy/testdata/acl-enabled-but-no-token.golden
command/connect/envoy/testdata/hcp-metrics.golden

Also command/connect/envoy/testdata/access-log-path.golden exists, but I think access logs were added in 1.15+?

[DanStough]

Yes, for sure the access log changes weren't introduced until 1.15. Spot checking the other files, they also look to be added in later releases.

FWIW the golden files were automatically updated using the -update flag when running the tests.