updated CI

Author: joaquintides

.github/workflows/ci.yml

@@ -38,22 +38,26 @@ jobs:
             address-model: 32,64
           - toolset: gcc-7
             cxxstd: "11,14,17"
-            os: ubuntu-20.04
+            container: ubuntu:20.04
+            os: ubuntu-latest
             install: g++-7-multilib
             address-model: 32,64
           - toolset: gcc-8
             cxxstd: "11,14,17,2a"
-            os: ubuntu-20.04
+            container: ubuntu:20.04
+            os: ubuntu-latest
             install: g++-8-multilib
             address-model: 32,64
           - toolset: gcc-9
             cxxstd: "11,14,17,2a"
-            os: ubuntu-20.04
+            container: ubuntu:20.04
+            os: ubuntu-latest
             install: g++-9-multilib
             address-model: 32,64
           - toolset: gcc-10
             cxxstd: "11,14,17,2a"
-            os: ubuntu-20.04
+            container: ubuntu:20.04
+            os: ubuntu-latest
             install: g++-10-multilib
             address-model: 32,64
           - toolset: gcc-11
@@ -99,31 +103,37 @@ jobs:
           - toolset: clang
             compiler: clang++-6.0
             cxxstd: "11,14,17"
-            os: ubuntu-20.04
+            os: ubuntu-latest
+            container: ubuntu:18.04
             install: clang-6.0
           - toolset: clang
             compiler: clang++-7
             cxxstd: "11,14,17"
-            os: ubuntu-20.04
+            os: ubuntu-latest
+            container: ubuntu:18.04
             install: clang-7
           - toolset: clang
             compiler: clang++-8
             cxxstd: "11,14,17"
-            os: ubuntu-20.04
+            os: ubuntu-latest
+            container: ubuntu:20.04
             install: clang-8
           - toolset: clang
             compiler: clang++-9
             cxxstd: "11,14,17,2a"
-            os: ubuntu-20.04
+            os: ubuntu-latest
+            container: ubuntu:20.04
             install: clang-9
           - toolset: clang
             compiler: clang++-10
             cxxstd: "11,14,17,2a"
-            os: ubuntu-20.04
+            os: ubuntu-latest
+            container: ubuntu:20.04
           - toolset: clang
             compiler: clang++-11
             cxxstd: "11,14,17,2a"
-            os: ubuntu-20.04
+            os: ubuntu-latest
+            container: ubuntu:20.04
           - toolset: clang
             compiler: clang++-12
             cxxstd: "11,14,17,20"