Upgrade Go version to 1.26.3

[github-actions]

Upgrade Go version to 1.26.3:
https://go.dev/doc/devel/release#go1.26.minor

• Set PR as "Ready for review"
• Check CI
• Submit PR review

[github-actions]

Overview

Image reference	score-compose:latest	score-compose:latest
- digest	505b0306e46a	fc21f20fc0c4
- tag	latest	latest
- provenance	4d586d4	cc0782e
- vulnerabilities
- platform	linux/amd64	linux/amd64
- size	6.3 MB	6.3 MB (+9.0 kB)
- packages	54	54

Policies (0 improved, 0 worsened)

Policy Name	score-compose:latest	score-compose:latest	Change	Standing
Default non-root user	✅	✅		No Change
No AGPL v3 licenses	✅	✅		No Change
No fixable critical or high vulnerabilities	✅	✅		No Change
No high-profile vulnerabilities	✅	✅		No Change
No outdated base images	✅	✅		No Change
No unapproved base images	✅	✅		No Change
Supply chain attestations	✅	✅		No Change
Valid Docker Hardened Image (DHI) or DHI base image	⚠️ 2	⚠️ 2		No Change

Packages and Vulnerabilities (10 package changes and 0 vulnerability changes)

• ♾️ 10 packages changed
• 44 packages unchanged

Changes for packages of type golang (10 changes)

	Package	Version score-compose:latest	Version score-compose:latest
♾️	github.com/docker/go-connections	0.6.0	0.7.0
♾️	github.com/masterminds/semver/v3	3.4.0	3.5.0
♾️	github.com/mattn/go-isatty	0.0.21	0.0.22
♾️	github.com/mattn/go-shellwords	1.0.12	1.0.13
♾️	github.com/olekukonko/errors	1.2.0	1.3.0
♾️	github.com/score-spec/score-compose	0.0.0-20260511131324-4d586d4c60da+dirty	0.0.0-20260511131612-cc0782e9ad92+dirty
♾️	github.com/tidwall/gjson	1.18.0	1.19.0
♾️	golang.org/x/crypto	0.49.0	0.51.0
♾️	golang.org/x/sys	0.43.0	0.44.0
♾️	golang.org/x/text	0.35.0	0.37.0

[mathieu-benoit]

LGTM