Fix cluster bootstrap when using a separate client node asg

[mch2]

Description

Currently an error is thrown that this tag must specify a value.

Error: Tag must have a value
    at new Tag (/Users/handalm/opensearch-cluster-cdk/node_modules/aws-cdk-lib/core/lib/tag-aspect.js:1:1498)
    at Tags.add (/Users/handalm/opensearch-cluster-cdk/node_modules/aws-cdk-lib/core/lib/tag-aspect.js:1:2705)
    at new InfraStack (/Users/handalm/opensearch-cluster-cdk/lib/infra/infra-stack.ts:655:32)
    at Object.<anonymous> (/Users/handalm/opensearch-cluster-cdk/bin/app.ts:46:20)
    at Module._compile (node:internal/modules/cjs/loader:1358:14)
    at Module.m._compile (/Users/handalm/opensearch-cluster-cdk/node_modules/ts-node/src/index.ts:1618:23)
    at Module._extensions..js (node:internal/modules/cjs/loader:1416:10)
    at Object.require.extensions.<computed> [as .ts] (/Users/handalm/opensearch-cluster-cdk/node_modules/ts-node/src/index.ts:1621:12)
    at Module.load (node:internal/modules/cjs/loader:1208:32)
    at Function.Module._load (node:internal/modules/cjs/loader:1024:12)

Issues Resolved

N/A

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