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This pull request includes several updates and improvements across multiple files, focusing on upgrading dependencies, enhancing logging, and refactoring code for better readability and maintainability. Below are the most important changes grouped by theme:

Dependency Upgrades:

• Updated the actions/setup-go action to version 5 and set the Go version to stable in .github/workflows/build.yml and .github/workflows/release.yml. [1] [2]
• Updated the goreleaser/goreleaser-action to version 6 in .github/workflows/release.yml.

Configuration and Build:

• Added a new configuration file .golangci.yml to enable specific linters and set exclusion rules for test files.
• Updated the Makefile to use the -trimpath flag in the build target and upgraded the Go version in dockertest and dockerinteg targets. [1] [2]

Logging Enhancements:

• Replaced the standard log package with log/slog for structured logging in cmd/process-exporter/main.go and collector/process_collector.go. [1] [2]
• Updated various logging statements to use the new logger and improved error handling in cmd/process-exporter/main.go. [1] [2]

Code Refactoring:

• Refactored flag handling in cmd/process-exporter/main.go to use kingpin for better command-line argument parsing.
• Replaced deprecated functions ioutil.TempFile and ioutil.ReadFile with os.CreateTemp and os.ReadFile respectively in cmd/load-generator/main.go and config/config.go. [1] [2]

Miscellaneous:

• Added build constraint //go:build linux to cmd/load-generator/main.go for specifying the target operating system.
• Simplified variable declarations and error handling in cmd/integration-tester/main.go. [1] [2]

These changes collectively aim to modernize the codebase, improve logging, and ensure compatibility with the latest tools and dependencies.