Update CI Linux builds to use GCC 10

GCC 8 doesn't support C++17's parallel algorithms, which I'd like to
use, and GCC 10 is the newest major version available from Ubuntu
20.04's repositories.

This commit removes a Linux-only std::filesystem::path constructor test,
which fails due to a thrown exception when compiled with GCC 10. The
failure isn't important, because libloot avoids that particular
constructor: in a sense an exception is a bit better because it would
make any usage more obvious.

.github/workflows/ci.yml

@@ -100,13 +100,13 @@ jobs:
             language-pack-el \
             language-pack-tr \
             libicu-dev \
-            g++-8
+            g++-10
 
       - name: Run CMake
         run: |
           mkdir build
           cd build
-          export CXX="g++-8" CC="gcc-8"
+          export CXX="g++-10" CC="gcc-10"
           cmake .. -DBOOST_ROOT="boost_1_78_0" -DCPACK_PACKAGE_VERSION="${{ steps.get-libloot-version.outputs.version }}"
           make all
 

.github/workflows/release.yml

@@ -67,13 +67,13 @@ jobs:
             language-pack-el \
             language-pack-tr \
             libicu-dev \
-            g++-8
+            g++-10
 
       - name: Run CMake
         run: |
           mkdir build
           cd build
-          export CXX="g++-8" CC="gcc-8"
+          export CXX="g++-10" CC="gcc-10"
           cmake .. -DBOOST_ROOT="boost_1_78_0" -DCPACK_PACKAGE_VERSION="${{ needs.create_release.outputs.git_tag }}"
           make all
 

src/tests/api/internals/main.cpp

@@ -116,21 +116,6 @@ TEST(Filesystem, pathStringConstructorUsesNativeEncodingOfUtf8) {
   EXPECT_EQ(utf8, path.u8string());
   EXPECT_EQ(utf16, path.u16string());
 }
-
-TEST(Filesystem,
-     pathStringAndLocaleConstructorUsesNativeEncodingOfUtf8WithCUtf8Locale) {
-  std::string utf8 = u8"Andr\u00E9_settings.toml";
-  std::u16string utf16 = u"Andr\u00E9_settings.toml";
-
-  ASSERT_EQ('\xc3', utf8[4]);
-  ASSERT_EQ('\xa9', utf8[5]);
-
-  std::filesystem::path path(utf8, std::locale("C.UTF-8"));
-
-  EXPECT_EQ(utf8, path.string());
-  EXPECT_EQ(utf8, path.u8string());
-  EXPECT_EQ(utf16, path.u16string());
-}
 #endif
 
 TEST(Filesystem, u8pathConvertsCharacterEncodingFromUtf8ToNative) {