chore(test): Improve localcluster tests speed and resiliency

[matthewmcneely]

Description

This PR improves the speed and resiliency on tests that rely on the LocalCluster system

• adds additional health and login checks to prevent timing issues with cluster creation
• parallel-izes some creation, login and health check functions to minimize delays
• adds support for using local dgraph image correctly when the DGRAPH_BINARY envar is present (tests on non-Linux systems that rely on running the native dgraph image would fail prior to this)
• suppresses expected "error" log output before defined thresholds (helps minimize false positives when checking logs)

Checklist

• Code compiles correctly and linting passes locally

[trunk-io]

     

Failed Test	Failure Summary	Logs
TestBackupOfOldRestore	The test failed because it could not establish a connection to retrieve predicate information.	Logs ↗︎

Flaky Test	Failure Summary	Logs
TestImportApis/SingleGroupShutOneAlpha	The test failed due to an error communicating with the Dgraph zero server, indicating that assigning IDs was attempted on a non-leader node.	Logs ↗︎
TestImportApis	The test 'TestImportApis' failed after running for a long duration.	Logs ↗︎

View Full Report ↗︎ ⋅ Docs

[Copilot]

Pull Request Overview

This PR improves the speed and resiliency of LocalCluster tests by parallelizing operations, enhancing health checks, and addressing timing issues.

• Parallelizes container creation, destruction, and health checks to reduce test execution time
• Increases timeout thresholds and improves error suppression to reduce false positives
• Adds support for native dgraph binaries via DGRAPH_BINARY environment variable

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
testutil/docker.go	Increases health check thresholds and adds attempt counters for better logging
dgraphtest/local_cluster.go	Parallelizes container operations and health checks using goroutines and wait groups
dgraphtest/load.go	Adds support for custom dgraph binary names via DGRAPH_BINARY environment variable
dgraphtest/image.go	Adds GOPATH validation and improves logging for binary setup
dgraph/cmd/dgraphimport/import_test.go	Adds comprehensive retry logic and helper functions for cluster stability

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[Copilot]

There is a spelling error in the comment. 'wheather' should be 'whether'.

Suggested change

	// CheckHealthContainer checks health of container and determines wheather container is ready to accept request
	// CheckHealthContainer checks health of container and determines whether container is ready to accept request