Add functional test for datasources at observability dashboards plugin

[RyanL1997]

Description

Add functional test for datasources at observability dashboards plugin

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[RyanL1997]

Facing the errors of OS set up step in observability e2e workflow (https://github.com/opensearch-project/opensearch-dashboards-functional-test/actions/runs/7402681376/job/20141042426?pr=987#step:6:13289):

Error: 1-03T21:40:09,706][ERROR][o.o.b.OpenSearchUncaughtExceptionHandler] [fv-az1016-625] uncaught exception in thread [main]
org.opensearch.bootstrap.StartupException: java.lang.IllegalStateException: failed to load plugin class [org.opensearch.security.OpenSearchSecurityPlugin]
	at org.opensearch.bootstrap.OpenSearch.init(OpenSearch.java:184) ~[opensearch-3.0.0.jar:3.0.0]
	at org.opensearch.bootstrap.OpenSearch.execute(OpenSearch.java:171) ~[opensearch-3.0.0.jar:3.0.0]
	at org.opensearch.cli.EnvironmentAwareCommand.execute(EnvironmentAwareCommand.java:104) ~[opensearch-3.0.0.jar:3.0.0]
	at org.opensearch.cli.Command.mainWithoutErrorHandling(Command.java:138) ~[opensearch-cli-3.0.0.jar:3.0.0]
	at org.opensearch.cli.Command.main(Command.java:101) ~[opensearch-cli-3.0.0.jar:3.0.0]
	at org.opensearch.bootstrap.OpenSearch.main(OpenSearch.java:137) ~[opensearch-3.0.0.jar:3.0.0]
	at org.opensearch.bootstrap.OpenSearch.main(OpenSearch.java:103) ~[opensearch-3.0.0.jar:3.0.0]
Caused by: java.lang.IllegalStateException: failed to load plugin class [org.opensearch.security.OpenSearchSecurityPlugin]
	at org.opensearch.plugins.PluginsService.loadPlugin(PluginsService.java:791) ~[opensearch-3.0.0.jar:3.0.0]
	at org.opensearch.plugins.PluginsService.loadBundle(PluginsService.java:731) ~[opensearch-3.0.0.jar:3.0.0]
	at org.opensearch.plugins.PluginsService.loadBundles(PluginsService.java:533) ~[opensearch-3.0.0.jar:3.0.0]
	at org.opensearch.plugins.PluginsService.<init>(PluginsService.java:195) ~[opensearch-3.0.0.jar:3.0.0]
	at org.opensearch.node.Node.<init>(Node.java:484) ~[opensearch-3.0.0.jar:3.0.0]
	at org.opensearch.node.Node.<init>(Node.java:411) ~[opensearch-3.0.0.jar:3.0.0]
	at org.opensearch.bootstrap.Bootstrap$5.<init>(Bootstrap.java:242) ~[opensearch-3.0.0.jar:3.0.0]
	at org.opensearch.bootstrap.Bootstrap.setup(Bootstrap.java:242) ~[opensearch-3.0.0.jar:3.0.0]
	at org.opensearch.bootstrap.Bootstrap.init(Bootstrap.java:404) ~[opensearch-3.0.0.jar:3.0.0]
	at org.opensearch.bootstrap.OpenSearch.init(OpenSearch.java:180) ~[opensearch-3.0.0.jar:3.0.0]
	... 6 more

[derek-ho]

Will be unblocked when #981 is merged

[RyanL1997]

The observability workflow is stucking there for 4+ hrs (See log: https://github.com/opensearch-project/opensearch-dashboards-functional-test/actions/runs/7506009472/job/20436491850?pr=987).

According to the above, I have run my code change on my local and here are the results:
Headless run in terminal:

Recorded video in browser:

7_datasources_dashboard.spec.js.mp4

(cc. @Hailong-am , @ruanyl , @wanglam )

[SuZhou-Joe]

stucking there for 4+ hrs
@RyanL1997 , I am sorry to say that Cypress(9.6.0) with latest Chrome/Chromium browser is using up the memory in github CI and thus hang the test case.

For now we recommend you post the test result in your local env as a workaround.

[opensearch-trigger-bot]

The backport to 2.x failed:

The process '/usr/bin/git' failed with exit code 1

To backport manually, run these commands in your terminal:

# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add .worktrees/backport-2.x 2.x
# Navigate to the new working tree
cd .worktrees/backport-2.x
# Create a new branch
git switch --create backport/backport-987-to-2.x
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 8cd68dc509eeb01ca7658f1f784201ce117cf009
# Push it to GitHub
git push --set-upstream origin backport/backport-987-to-2.x
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-2.x

Then, create a pull request where the base branch is 2.x and the compare/head branch is backport/backport-987-to-2.x.