From 6cb92871ffbf630f2d49e14a228edd22b614293c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Rafa=C5=82=20Mikrut?=
 <41945903+qarmin@users.noreply.github.com>
Date: Thu, 14 Jan 2021 13:26:43 +0100
Subject: [PATCH] Use the oldest available OS in Linux and Mac CI and the
 newest on Windows (#206)

---
 .github/workflows/linux.yml   | 4 ++--
 .github/workflows/mac.yml     | 4 ++--
 .github/workflows/windows.yml | 4 ++--
 3 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/.github/workflows/linux.yml b/.github/workflows/linux.yml
index 1f8ceea..cd13e30 100644
--- a/.github/workflows/linux.yml
+++ b/.github/workflows/linux.yml
@@ -10,7 +10,7 @@ jobs:
       matrix:
         toolchain: [ stable ]
         type: [ release ]
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
     steps:
       - uses: actions/checkout@v2
 
@@ -128,7 +128,7 @@ jobs:
       matrix:
         toolchain: [ stable ]
         type: [ release ]
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
     steps:
       - uses: actions/checkout@v2
 
diff --git a/.github/workflows/mac.yml b/.github/workflows/mac.yml
index f076ac2..c37fa03 100644
--- a/.github/workflows/mac.yml
+++ b/.github/workflows/mac.yml
@@ -10,7 +10,7 @@ jobs:
       matrix:
         toolchain: [ stable ]
         type: [ release ]
-    runs-on: macos-latest
+    runs-on: macos-10.15
     steps:
       - uses: actions/checkout@v2
 
@@ -53,7 +53,7 @@ jobs:
       matrix:
         toolchain: [ stable ]
         type: [ release ]
-    runs-on: macos-latest
+    runs-on: macos-10.15
     steps:
       - uses: actions/checkout@v2
 
diff --git a/.github/workflows/windows.yml b/.github/workflows/windows.yml
index 75806eb..9e87288 100644
--- a/.github/workflows/windows.yml
+++ b/.github/workflows/windows.yml
@@ -10,7 +10,7 @@ jobs:
       matrix:
         toolchain: [ stable ]
         type: [ release ]
-    runs-on: windows-latest
+    runs-on: windows-2019
     steps:
       - uses: actions/checkout@v2
 
@@ -149,7 +149,7 @@ jobs:
       matrix:
         toolchain: [ stable ]
         type: [ release ]
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-20.04
     steps:
       - uses: actions/checkout@v2