Upgrade CI elixir/erlang and bump minimum to 1.15 (#230)

Author: alisinabh

.github/workflows/elixir.yml

@@ -27,17 +27,17 @@ jobs:
     strategy:
       matrix:
         variation:
-          - otp: "27.x"
-            elixir: "1.18"
+          - otp: "28.x"
+            elixir: "1.19"
             report_coverage: true
-          - otp: "26.x"
+          - otp: "27.x"
+            elixir: "1.19"
+            report_coverage: false
+          - otp: "28.x"
             elixir: "1.18"
             report_coverage: false
           - otp: "27.x"
-            elixir: "1.17"
-            report_coverage: false
-          - otp: "26.x"
-            elixir: "1.17"
+            elixir: "1.18"
             report_coverage: false
 
     steps:

mix.exs

@@ -8,7 +8,7 @@ defmodule Ethers.MixProject do
     [
       app: :ethers,
       version: @version,
-      elixir: "~> 1.11",
+      elixir: "~> 1.15",
       elixirc_paths: elixirc_paths(Mix.env()),
       start_permanent: Mix.env() == :prod,
       name: "Ethers",