Update Elixir to 1.19.3 and Erlang/OTP to 28.2

[Copilot]

Updates runtime and CI to latest versions.

Changes

• .tool-versions: Elixir 1.19.3-otp-28, Erlang 28.2
• CI matrix: Tests against OTP 28.2 (latest) and 27.3 (compatibility)

Updated from Elixir 1.19.2 to 1.19.3 and Erlang 28.1.1 to 28.2. CI upgraded from testing 1.17.3+1.18.3 on OTP 27.3 to testing 1.19.3 on both OTP 27.3 and 28.2.

Original prompt

Can you create a pull request with Elixir and Erlang updated to latest versions?

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[royalicing]

We've gone backwards

[Copilot]

Fixed in 00d0aed - updated to Elixir 1.19.3 (I had incorrectly downgraded to 1.18.3)

[Copilot]

Just as a heads up, I was blocked by some firewall rules while working on your feedback. Expand below for details.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• https://api.github.com/repos/elixir-lang/elixir/releases
  • Triggering command: /usr/bin/curl curl -s REDACTED (http block)
• https://api.github.com/repos/erlang/otp/releases
  • Triggering command: /usr/bin/curl curl -s REDACTED (http block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)