Update ubuntu Docker tag to v26

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
ubuntu (source)	final	major	24.04 → 26.04
ubuntu (source)	stage	major	24.04 → 26.04

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Configuration

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[coveralls]

Coverage Report for CI Build 35723969254

Coverage remained the same at 91.609%

Details

• Coverage remained the same as the base build.
• Patch coverage: No coverable lines changed in this PR.
• No coverage regressions found.

Uncovered Changes

No uncovered changes found.

Coverage Regressions

No coverage regressions found.

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Coverage Stats

Relevant Lines:	727
Covered Lines:	666
Line Coverage:	91.61%
Coverage Strength:	8.24 hits per line

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💛 - Coveralls