Require Elixir v1.10

We've recently added a test [1] [2] that fails due to compiler bugs on
1.7 [3] and 1.8-1.9 [4].

[1] 9bfcdd8
[2] fc08a53
[3] https://github.com/elixir-lang/ex_doc/runs/1213878993
[4] https://github.com/elixir-lang/ex_doc/runs/1213879027

Author: wojtekmach

.github/workflows/ci.yml

@@ -13,12 +13,6 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - otp: 19.3.6.13
-            elixir: 1.7.4
-          - otp: 20.3.8.26
-            elixir: 1.8.2
-          - otp: 20.3.8.26
-            elixir: 1.9.4
           - otp: 21.3.8.16
             elixir: 1.10.3
           - otp: 23.0.2

CHANGELOG.md

@@ -1,5 +1,9 @@
 # Changelog
 
+## HEAD
+
+Require Elixir v1.10.
+
 ## v0.22.6 (2020-09-16)
 
   * Bug fix

mix.exs

@@ -7,7 +7,7 @@ defmodule ExDoc.Mixfile do
     [
       app: :ex_doc,
       version: @version,
-      elixir: "~> 1.7",
+      elixir: "~> 1.10",
       deps: deps(),
       aliases: aliases(),
       package: package(),