Changes grants from String to ArrayList

[Kirishikesan]

Overview

The pack was storing the grants in String data type with spaces as delimiters and querying the grants. Even when the grant types which are present as substrings, it was detected as present. This PR stores grants as an ArrayList instead of String

Resolves :

wso2/api-manager#2094

[CLAassistant]

All committers have signed the CLA.

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PR builder completed
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Status: failure

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PR builder started
Link: https://github.com/wso2/product-is/actions/runs/5899153567

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PR builder completed
Link: https://github.com/wso2/product-is/actions/runs/5899153567
Status: failure

[nilasini]

Since the failure is not related with this PR, merging this PR.

[ERROR] org.wso2.identity.integration.test.sts.TestPassiveSTS.testPassiveSAML2Assertion(org.wso2.identity.integration.test.sts.TestPassiveSTS)
 [ERROR] Run 1: TestPassiveSTS.testPassiveSAML2Assertion:268 No SAML2 Assertion found for the SAML2 request for tenant domain: carbon.super expected:<true> but was:<false>
 [INFO] Run 2: PASS
 [INFO] 
 [ERROR] org.wso2.identity.integration.test.sts.TestPassiveSTS.testPassiveSAML2AssertionForInvalidWReply(org.wso2.identity.integration.test.sts.TestPassiveSTS)
 [ERROR] Run 1: TestPassiveSTS.testPassiveSAML2AssertionForInvalidWReply:319 Cannot find soap fault for invalid WReply URL for tenant domain: carbon.super expected:<true> but was:<false>
 [INFO] Run 2: PASS
 [INFO] 
 [ERROR] org.wso2.identity.integration.test.sts.TestPassiveSTS.testPassiveSAML2AssertionWithoutWReply(org.wso2.identity.integration.test.sts.TestPassiveSTS)
 [ERROR] Run 1: TestPassiveSTS.testPassiveSAML2AssertionWithoutWReply:292 No SAML2 Assertion found for the SAML2 request without WReply in passive-sts request for tenant domain: carbon.super expected:<true> but was:<false>
 [INFO] Run 2: PASS
 [INFO] 
 [INFO] 
 [ERROR] Tests run: 1994, Failures: 3, Errors: 0, Skipped: 0