Fix: fix broken test PkgGeneratorTest

[SSE4]

noticed in #6809, seems to be side-effect of #7059
seems like CI wasn't running for some time today (due to the bots changing their permissions), as result we have had develop branch broken for a while
/cc @jgsogo @danimtb

Changelog: Fix: Fix broken test PkgGeneratorTest.
Docs: omit

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[jgsogo]

It looks like a side effect of i+2 --> i+1 (https://github.com/conan-io/conan/pull/7059/files#diff-3cc8c2ecd6bb571809dd1ecc646f1a63L117)