Update ubuntu version

[Pearl1594]

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[Copilot]

Pull Request Overview

This PR updates the project from Ubuntu 20.04 to Ubuntu 24.04 and Go 1.21 to Go 1.23, along with implementing comprehensive snapshot management functionality including listing, validation, and enhanced error handling.

• Updated Ubuntu version from 20.04 to 24.04 across GitHub workflows
• Upgraded Go version from 1.21 to 1.23 with toolchain specification
• Added complete snapshot lifecycle management with listing, validation, and improved error handling

Reviewed Changes

Copilot reviewed 11 out of 11 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
.github/workflows/release.yaml	Updated Ubuntu runner from 20.04 to 24.04
.github/workflows/pr-check.yaml	Updated Ubuntu runner and Go version from 1.15 to 1.23, updated golangci-lint version
go.mod	Updated Go version to 1.23 with toolchain, moved protobuf dependency to required section
pkg/mount/mount.go	Added blank lines for readability, removed duplicate function, added gosec linter exclusions
pkg/driver/controller.go	Added ListSnapshots implementation, enhanced CreateSnapshot validation, improved error handling
pkg/cloud/volumes.go	Removed domainID parameter from CreateVolumeFromSnapshot function
pkg/cloud/vms.go	Added blank line for code formatting
pkg/cloud/snapshots.go	Enhanced snapshot functions with name support, added GetSnapshotByName and ListSnapshots
pkg/cloud/fake/fake.go	Implemented comprehensive fake snapshot management for testing
pkg/cloud/config.go	Updated import alias for gcfg package
pkg/cloud/cloud.go	Updated interface signatures and added ErrAlreadyExists error type

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[vishesh92]

code looks good to me