chore(tests): use a LTS JENKINS_VERSION for expected_tags_latest_lts

[lemeurherve]

This PR uses a LTS JENKINS_VERSION for a more realistic expected_tags_latest_lts test, which should have used a LTS JENKINS_VERSION since its introduction.

Extracted from:

• chore: allow to differenciate JDKs to build depending on Jenkins release line #2178 (comment)

Amends:

• chore: introduce golden file testing of tags #2134

Ref:

• Use golden files for testing tags to prevent regression when changing docker bake file #2135

Testing done

bats ./tests/bake.bats 
bake.bats
 ✓ [docker bake: tags] Default tags unchanged
 ✓ [docker bake: tags] Latest weekly tags unchanged
 ✓ [docker bake: tags] Latest LTS tags unchanged
 ✓ [docker bake: platforms] Platforms per target unchanged

4 tests, 0 failures

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