Adding TOKEN as header to curl command for INSTANCE_ROLE and Region

[rishij39]

Issue #, if available:
credential.sh was failing to set INSTANCE_ROLE and Region env variables
Description of changes:
Adding TOKEN as header to curl command for INSTANCE_ROLE and Region

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[tebanieo]

I confirmed the current credentials.sh is returning an error

WSParticipantRole:~/environment/OpenSearchPipeline $ . ./credentials.sh parse error: Invalid numeric literal at line 2, column 0 parse error: Invalid numeric literal at line 2, column 0 parse error: Invalid numeric literal at line 2, column 0 METADATA_AWS_ACCESS_KEY_ID: METADATA_AWS_SECRET_ACCESS_KEY: METADATA_AWS_SESSION_TOKEN: METADATA_AWS_REGION: METADATA_AWS_ROLE: <REDACTED>role/ddb-Cloud9Role-0WaehjdX3PJC 

and the suggested solution will fix it.

WSParticipantRole:~/environment/OpenSearchPipeline $ . ./credentials.sh METADATA_AWS_ACCESS_KEY_ID: ASIA3Q<REDACTED> METADATA_AWS_SECRET_ACCESS_KEY: gsY3jAXO<REDACTED> METADATA_AWS_SESSION_TOKEN: <REDACTED> METADATA_AWS_REGION: us-west-2 METADATA_AWS_ROLE: <REDACTED>role/ddb-Cloud9Role-0WaehjdX3PJC