Update DependabotSecretsSelectedRepoIDs type to []int64

[jburandt]

According to the docs, the API for setting a repos access to dependabot secrets is expecting an array of integers.

https://docs.github.com/en/rest/dependabot/secrets?apiVersion=2022-11-28#set-selected-repositories-for-an-organization-secret

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[gmlewis]

Thank you, @jburandt !
LGTM.

Awaiting second LGTM+Approval from any other contributor to this repo before merging.

[codecov]

Codecov Report

Merging #2794 (c800c9f) into master (d6880db) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #2794   +/-   ##
=======================================
  Coverage   98.06%   98.06%           
=======================================
  Files         132      132           
  Lines       11650    11650           
=======================================
  Hits        11424    11424           
  Misses        154      154           
  Partials       72       72           

Impacted Files	Coverage Δ
github/dependabot_secrets.go	100.00% <ø> (ø)

[valbeat]

LGTM!

[gmlewis]

Thank you, @valbeat !
Merging.