Bump Elixir/Erlang version in mix.exs and Heroku buildpack config

.gitlab-ci.yml

@@ -1,4 +1,4 @@
-image: elixir:1.9.4
+image: elixir:1.11
 
 variables: &global_variables
   POSTGRES_DB: pleroma_test
@@ -157,8 +157,12 @@ analysis:
 
 cycles:
   stage: test
-  image: elixir:1.11
-  cache: {}
+  only:
+    changes:
+      - "**/*.ex"
+      - "**/*.exs"
+      - "mix.lock"
+  cache: *testing_cache_policy
   script:
     - mix deps.get
     - mix compile
@@ -238,7 +242,7 @@ stop_review_app:
 
 amd64:
   stage: release
-  image: elixir:1.10.3
+  image: elixir:1.11
   only: &release-only
   - stable@pleroma/pleroma
   - develop@pleroma/pleroma
@@ -276,7 +280,7 @@ amd64-musl:
   stage: release
   artifacts: *release-artifacts
   only: *release-only
-  image: elixir:1.10.3-alpine
+  image: elixir:1.11-alpine
   cache: *release-cache
   variables: *release-variables
   before_script: &before-release-musl
@@ -292,7 +296,7 @@ arm:
   only: *release-only
   tags:
     - arm32-specified
-  image: arm32v7/elixir:1.10.3
+  image: arm32v7/elixir:1.11
   cache: *release-cache
   variables: *release-variables
   before_script: *before-release
@@ -304,7 +308,7 @@ arm-musl:
   only: *release-only
   tags:
     - arm32-specified
-  image: arm32v7/elixir:1.10.3-alpine
+  image: arm32v7/elixir:1.11-alpine
   cache: *release-cache
   variables: *release-variables
   before_script: *before-release-musl
@@ -316,7 +320,7 @@ arm64:
   only: *release-only
   tags:
     - arm
-  image: arm64v8/elixir:1.10.3
+  image: arm64v8/elixir:1.11
   cache: *release-cache
   variables: *release-variables
   before_script: *before-release
@@ -328,7 +332,7 @@ arm64-musl:
   only: *release-only
   tags:
     - arm
-  image: arm64v8/elixir:1.10.3-alpine
+  image: arm64v8/elixir:1.11-alpine
   cache: *release-cache
   variables: *release-variables
   before_script: *before-release-musl

elixir_buildpack.config

@@ -1,2 +1,2 @@
-elixir_version=1.9.4
-erlang_version=22.3.4.1
+elixir_version=1.11
+erlang_version=23.3.4.2

mix.exs

@@ -5,7 +5,7 @@ defmodule Pleroma.Mixfile do
     [
       app: :pleroma,
       version: version("2.3.50"),
-      elixir: "~> 1.9",
+      elixir: "~> 1.11",
       elixirc_paths: elixirc_paths(Mix.env()),
       compilers: [:phoenix, :gettext] ++ Mix.compilers(),
       elixirc_options: [warnings_as_errors: warnings_as_errors(Mix.env())],