check throttling endpoint coverage against scan.yaml

[stephencompall-DA]

If you've missed endpoint coverage you'll get an error in GHA deployment_test, e.g.

Error: Rate limit configuration errors:
- Missing rate limit prefixes for scan.yaml endpoints: /api/scan/readyz
    at validateEffectiveRateLimits (/Users/stephencompall/ide/splice/cluster/pulumi/common/src/ratelimit/envoyRateLimiter.ts:127:11)
️✂️✂️✂️<snip>✂️✂️✂️
make: *** [/Users/stephencompall/ide/splice/cluster/pulumi/pulumi-test-clusters.mk:6: cluster/pulumi/canton-network/test.json] Error 1

You can also see this in canton-network preview; here is a misspelling of endpoint prefix, for example:

error: Error: Rate limit configuration errors:
- Missing rate limit prefixes for scan.yaml endpoints: /api/scan/readyz
- Orphaned rate limit prefixes not matching any scan.yaml endpoint: /api/scan/redyz

From this configuration, the pulumi diff to expect is from canton-network, one per sv, like so:

    ~ splice:RateLimit: (update)
        [urn=urn:pulumi:canton-network.scratchd::canton-network::splice:RateLimit::splice-sv-da-1-scan-app-rate-limit]
        appLabel    : "scan-app"
        globalLimits: {
            fillInterval : "60s"
            maxTokens    : 2147483647
            tokensPerFill: 2147483647
        }
        inboundPort : 5012
        namespace   : "sv-da-1"
      ~ rateLimits  : [
️✂️✂️✂️<a bunch of new appended items>✂️✂️✂️

It does not imply the creation of new EnvoyFilters, which are the actual filters.

Fixes DACH-NY/canton-network-internal#3697.

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