ci: update golangci-lint to v2

[PascalBourdier]

update method:

golangci-lint migrate
golangci-lint run --fix

and fix the last ones manually

[Copilot]

Pull request overview

This PR updates golangci-lint from v1 to v2, applying automated linting fixes and migrating the configuration format. The changes align the codebase with modern Go conventions and golangci-lint v2 requirements.

• Updates golangci-lint configuration to v2 format with separated linters and formatters sections
• Standardizes error messages to follow Go conventions (lowercase start, no trailing periods)
• Modernizes string operations by replacing strings.Replace(..., -1) with strings.ReplaceAll()

Reviewed changes

Copilot reviewed 19 out of 19 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
.golangci.yml	Migrates configuration to v2 format, separates formatters from linters
.github/workflows/ci.yaml	Updates golangci-lint-action to v9 and version to v2.6.2
testing/docker.go	Lowercases error message starts (5 instances)
source/gitlab/gitlab.go	Simplifies embedded struct field access
internal/cli/commands.go	Lowercases error messages and improves punctuation
database/testing/testing.go	Lowercases error message start
database/sqlserver/sqlserver.go	Removes trailing period from error message
database/snowflake/snowflake.go	Replaces strings.Replace with strings.ReplaceAll
database/redshift/redshift.go	Replaces strings.Replace with strings.ReplaceAll
database/redshift/redshift_test.go	Updates test code to use strings.ReplaceAll
database/postgres/postgres.go	Lowercases error messages and uses strings.ReplaceAll
database/postgres/postgres_test.go	Updates test code to use strings.ReplaceAll
database/pgx/v5/pgx.go	Lowercases error messages and uses strings.ReplaceAll (2 locations)
database/pgx/v5/pgx_test.go	Updates test code to use strings.ReplaceAll
database/pgx/pgx.go	Lowercases error messages and uses strings.ReplaceAll (3 locations)
database/pgx/pgx_test.go	Updates test code to use strings.ReplaceAll
database/mysql/mysql.go	Lowercases error message start
database/clickhouse/clickhouse.go	Replaces strings.Replace with strings.ReplaceAll
database/cassandra/cassandra.go	Lowercases error message start

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[Copilot]

Pull request overview

Copilot reviewed 19 out of 19 changed files in this pull request and generated 1 comment.

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[coveralls]

coverage: 54.432%. remained the same
when pulling c7ff14f on PascalBourdier:golangcilintv2
into 89e308c on golang-migrate:master.