fix(ec2-metadata-service): add configurable options for ttl and port precedence

[siddsriv]

Issue

Internal JS-5193

Description

makes tokenTtl configurable and sets a precedence order for port.

Testing

unit testing:

✓ src/MetadataService.spec.ts (31 tests) 23ms
   ✓ MetadataService Socket Leak Checks > fetchMetadataToken - body consumption checks > should consume response body on 200 status and return token 5ms
   ✓ MetadataService Socket Leak Checks > fetchMetadataToken - body consumption checks > should consume response body on 400 status before throwing 2ms
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   ✓ MetadataService Retry Configuration > status code handling for retries > should retry 500 errors 0ms
   ✓ MetadataService Token TTL Configuration > should use default tokenTtl of 21600 seconds 0ms
   ✓ MetadataService Token TTL Configuration > should use custom tokenTtl value 0ms
   ✓ MetadataService Token TTL Configuration > should validate tokenTtl as positive integer 1ms
   ✓ MetadataService Token TTL Configuration > should accept valid positive integer tokenTtl values 0ms
   ✓ MetadataService Token TTL Configuration > should convert tokenTtl to string in header 0ms

 Test Files  1 passed (1)
      Tests  31 passed (31)

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[kuhe]

shouldn't it default to undefined or the default port of the url's protocol?