Closes CH-144

Added a new flag to the deploy/helm/flags/install array of the skaffold template

Unit tests added to the test_skaffold.py file in ch_cli_tools, any skaffold.yaml generated with harness-deployment should include a --timeout=10m flag in the deploy/helm/flags/install array.

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Sanity checks:

[x] The pull request is explicitly linked to the relevant issue(s)
[x] The issue is well described: clearly states the problem and the general proposed solution(s)
[x] In this PR it is explicitly stated how to test the current change
[x] The labels in the issue set the scope and the type of issue (bug, feature, etc.)
[x] The relevant components are indicated in the issue (if any)
[x] All the automated test checks are passing
[x] All the linked issues are included in one Sprint
[x] All the linked issues are in the Review state
[x] All the linked issues are assigned

Breaking changes (select one):

[x] The present changes do not change the preexisting api in any way
[ ] This PR and the issue are tagged as a breaking-change and the migration procedure is well described above

Possible deployment updates issues (select one):

[x] There is no reason why deployments based on CloudHarness may break after the current update
[ ] This PR and the issue are tagged as alert:deployment

Test coverage (select one):

[x] Tests for the relevant cases are included in this pr
[ ] The changes included in this pr are out of the current test coverage scope

Documentation (select one):

[ ] The documentation has been updated to match the current changes
[x] The changes included in this PR are out of the current documentation scope

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[ ] Screenshots of the changes
[ ] Explanatory video/animated gif

MetaCell / cloud-harness