configure SLH size for ZSS to handle file size greater than 6mb

Proposed changes

The heap available to the http server is currently capped to around 6MB, because of this there is a limit in the size of the dataset that can be uploaded using ZSS API's. To solve this, we are providing an option in configuration under 'components ->zss ->httpHeapMaxBlocks'. By default it would be 1024 meaning, 64KB 1024, and as of now we have capped the max value of this option to be 4096 meaning, 64kb 4096.

This PR addresses Issue: https://github.com/zowe/zss/issues/698

This PR depends upon the following PRs: https://github.com/zowe/zowe-common-c/pull/447

Type of change

Please delete options that are not relevant.

[x] Bug fix (non-breaking change which fixes an issue)
[x] New feature (non-breaking change which adds functionality)
[ ] Change in a documentation
[ ] Refactor the code
[x] Chore, repository cleanup, updates the dependencies.

PR Checklist

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[x] If the changes in this PR are meant for the next release / mainline, this PR targets the "staging" branch.
[x] My code follows the style guidelines of this project (see: Contributing guideline)
[x] I have commented my code, particularly in hard-to-understand areas
[] I have made corresponding changes to the documentation
[x] New and existing unit tests pass locally with my changes
[x] video or image is included if visual changes are made
[x] Relevant update to CHANGELOG.md
[x] My changes generate no new warnings
[x] I have added tests that prove my fix is effective or that my feature works, or describe a test method below

Testing

You can try with uploading a dataset with size greater than 6mb using a python script.

Further comments

zowe-common-c is pointing to the latest changes.

zowe / zss