fix: indexing and seasonal_periods check that endog is at least twice the size

[Lopa10ko]

This is a 🔥 hotfix.

Summary

• Add seasonal_periods check that endog is at least twice the size (a79d3d3)
• Set proper index array size (c53af7a)

Context

related to https://github.com/aimclub/FEDOT/actions/runs/9499709347 integration workflow failure
related to #1297

[docu-mentor]

👋 Hi, I'm @Docu-Mentor, an LLM-powered GitHub app
powered by Anyscale Endpoints
that gives you actionable feedback on your writing.

Simply create a new comment in this PR that says:

@Docu-Mentor run

and I will start my analysis. I only look at what you changed
in this PR. If you only want me to look at specific files or folders,
you can specify them like this:

@Docu-Mentor run doc/ README.md

In this example, I'll have a look at all files contained in the "doc/"
folder and the file "README.md". All good? Let's get started!

[github-actions]

Code has no PEP8 errors!