feat(experimentalIdentityAndAuth): add getEndpointParameterInstructions() to smithy context

[syall]

Issue #, if available:

N/A.

Description of changes:

Add getEndpointParameterInstructions() to smithy context.

Testing:

Note: all of the changes are gated by experimentalIdentityAndAuth flag

The codegen diff adds the endpointRuleSet context with the getEndpointParameterInstructions per operation, and will be used in the S3 and EventBridge @endpointRuleset HttpAuthSchemeProviders in aws/aws-sdk-js-v3#5231.

diff --color -Nur /Users/yuasteve/development/ts-ia/smithy-typescript/smithy-typescript-codegen-test/build_old/smithyprojections/smithy-typescript-codegen-test/client-experimental-identity-and-auth/typescript-codegen/src/commands/CreateCityCommand.ts /Users/yuasteve/development/ts-ia/smithy-typescript/smithy-typescript-codegen-test/build/smithyprojections/smithy-typescript-codegen-test/client-experimental-identity-and-auth/typescript-codegen/src/commands/CreateCityCommand.ts
--- /Users/yuasteve/development/ts-ia/smithy-typescript/smithy-typescript-codegen-test/build_old/smithyprojections/smithy-typescript-codegen-test/client-experimental-identity-and-auth/typescript-codegen/src/commands/CreateCityCommand.ts	2023-09-24 00:00:25
+++ /Users/yuasteve/development/ts-ia/smithy-typescript/smithy-typescript-codegen-test/build/smithyprojections/smithy-typescript-codegen-test/client-experimental-identity-and-auth/typescript-codegen/src/commands/CreateCityCommand.ts	2023-09-24 00:02:02
@@ -101,6 +101,9 @@
       [SMITHY_CONTEXT_KEY]: {
         service: "Weather",
         operation: "CreateCity",
+        endpointRuleSet: {
+          getEndpointParameterInstructions: CreateCityCommand.getEndpointParameterInstructions,
+        },
       },
     }
     const { requestHandler } = configuration;

If one or more of the packages in the /packages directory has been modified, be sure yarn changeset add has been run and its output has
been committed and included in this pull request. See CONTRIBUTING.md.

---

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[syall]

Closed in favor of: #956, #957, aws/aws-sdk-js-v3#5231