[FEATURE] Remove push event triggers in all workflow

[SuZhou-Joe]

Is your feature request related to a problem?

The push triggered flow fails to launch as it requests checkout action first before doing path-filter.

What solution would you like?

Remove the useless push event as all the commit happens with a pull request, we do not allow contributors to push to a branch directly.

What alternatives have you considered?

A clear and concise description of any alternative solutions or features you've considered.

Do you have any additional context?

https://github.com/opensearch-project/opensearch-dashboards-functional-test/actions/runs/7938831230/job/21678772804?pr=1107

[wanglam]

@SuZhou-Joe Will the pull request events re-run after new commits pushed?

[Hailong-am]

pull event might be useful for fork repos to test changes. Also @ruanyl have a PR #1017 to solve similar issue.

[SuZhou-Joe]

pull event might be useful for fork repos to test changes. Also @ruanyl have a PR #1017 to solve similar issue.

I see, didn't know that.

[ruanyl]

Closing this issue as it's fixed in #1017