CI: remove InsignificantTestsflag for two CentOS 8.1

Task-number: QTQAINFRA-2760
Task-number: QTQAINFRA-3065
Change-Id: Ic221b9c63ddfe5b5f62e3900f11fa0a27371e401
Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>

coin/platform_configs/cmake_platforms.yaml

@@ -80,7 +80,7 @@ Configurations:
     Id: 'CentOS-8.1-host'
     Template: 'qtci-linux-CentOS-8.1-x86_64-50'
     Compiler: 'GCC'
-    Features: ['Packaging', 'Sccache', 'InsignificantTests']
+    Features: ['Packaging', 'Sccache']
     Configure arguments: '-DBUILD_EXAMPLES=OFF -DCMAKE_BUILD_TYPE=RelWithDebInfo -DFEATURE_separate_debug_info=ON -DFEATURE_system_jpeg=OFF -DFEATURE_system_png=OFF -DFEATURE_system_pcre2=OFF -DFEATURE_system_harfbuzz=OFF -DFEATURE_system_doubleconversion=OFF -DFEATURE_libudev=OFF -DCMAKE_C_COMPILER_LAUNCHER=sccache -DCMAKE_CXX_COMPILER_LAUNCHER=sccache'
     Environment variables: ['NON_QTBASE_CONFIGURE_ARGS=-DCMAKE_C_COMPILER_LAUNCHER=sccache -DCMAKE_CXX_COMPILER_LAUNCHER=sccache',
         'TEST_CONFIGURE_ARGS=-DCMAKE_C_COMPILER_LAUNCHER=sccache -DCMAKE_CXX_COMPILER_LAUNCHER=sccache']

coin/platform_configs/default.yaml

@@ -34,7 +34,7 @@ Configurations:
 -
     Template: 'qtci-linux-CentOS-8.1-x86_64-50'
     Compiler: 'GCC'
-    Features: ['UseLegacyInstructions', 'InsignificantTests']
+    Features: ['UseLegacyInstructions']
     Configure arguments: '-qmake -opensource -confirm-license -verbose -prefix /home/qt/work/install -release -nomake tests -nomake examples -no-libudev -no-use-gold-linker -headersclean -force-debug-info -separate-debug-info -no-sql-mysql -plugin-sql-psql -plugin-sql-sqlite -qt-libjpeg -qt-libpng -xcb -bundled-xcb-xinput -sysconfdir /etc/xdg -openssl -qt-pcre -qt-harfbuzz -R . QMAKE_LFLAGS_APP+=-s'
 -
     Template: 'qtci-macos-10.14-x86_64'