Add basic CI github action

[axelson]

Description

Adds GitHub actions as CI to ensure that any pull requests pass all of our CI checks

Tests are run on OTP 24.2 which is the lowest version of OTP that is supported by Ubuntu 22.04 by erlef/setup-beam: https://github.com/erlef/setup-beam#compatibility-between-operating-system-and-erlangotp

Failing tests are successfully found: https://github.com/ScenicFramework/scenic/actions/runs/5231301605/jobs/9445365052?pr=318

There's many warnings printed while running the tests, but I think we can wait and fix those in a followup PR:

Error: 18:13:54.431 [error] GenServer #PID<0.3409.0> terminating
** (ArgumentError) argument error
    (stdlib 3.17) :ets.lookup(#Reference<0.2423467283.3612475393.247207>, "ctU_DlJdXEYBxRzNU77waQ")
    (scenic 0.11.1) lib/scenic/view_port.ex:269: Scenic.ViewPort.get_script/2
    (scenic 0.11.1) lib/scenic/view_port.ex:374: Scenic.ViewPort.put_graph/4
    (scenic 0.11.1) lib/scenic/scene.ex:864: Scenic.Scene.push_graph/3
    (scenic 0.11.1) lib/scenic/component/input/caret.ex:179: Scenic.Component.Input.Caret.handle_cast/2
    (stdlib 3.17) gen_server.erl:695: :gen_server.try_dispatch/4
    (stdlib 3.17) gen_server.erl:771: :gen_server.handle_msg/6
    (stdlib 3.17) proc_lib.erl:226: :proc_lib.init_p_do_apply/3
Last message: {:"$gen_cast", :reset_caret}
State: %Scenic.Scene{assigns: %{focused: true, graph: %Scenic.Graph{add_to: 0, animations: [], ids: %{_root_: [0], caret: [1]}, next_uid: 2, primitives: %{0 => %Scenic.Primitive{data: [1], default_pin: {0, 0}, id: :_root_, module: Scenic.Primitive.Group, opts: [], parent_uid: -1, styles: %{}, transforms: %{}}, 1 => %Scenic.Primitive{data: {{0, 4}, {0, 26.0}}, default_pin: {0.0, 15.0}, id: :caret, module: Scenic.Primitive.Line, opts: [], parent_uid: 0, styles: %{hidden: false, stroke: {2, {:color, {:color_rgba, {244, 164, 96, 255}}}}}, transforms: %{}}}}, hidden: false, timer: {:interval, #Reference<0.2423467283.3612344322.239828>}}, child_supervisor: nil, children: nil, id: "ctU_DlJdXEYBxRzNU77waQ", module: Scenic.Component.Input.Caret, parent: #PID<0.3401.0>, pid: #PID<0.3409.0>, stop_pid: #PID<0.3409.0>, supervisor: #PID<0.3400.0>, theme: :dark, viewport: %Scenic.ViewPort{name: nil, pid: #PID<0.3383.0>, script_table: #Reference<0.2423467283.3612475393.247207>, size: {700, 600}}

Motivation and Context

Previously Scenic was using Travis but Travis has severely limited their free plan.

Types of changes

• [ ] Bug fix (a non-breaking change which fixes an issue)
• [ ] New feature (a non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
• [x] Improvement/refactoring (non-breaking change that doesn't add any feature but make things better)

Checklist

• [x] Check other PRs and make sure that the changes are not done yet.