Rename xunit config for System.Globalization.Calendars (dotnet/corefx#32020)

Commit migrated from https://github.com/dotnet/corefx/commit/68b76c30eafb3647c11e3f766a2645b130ca1448

diff --git a/src/libraries/System.Globalization.Calendars/tests/CalendarTestWithConfigSwitch/coverage/xunit.console.netcore.runtimeconfig.json b/src/libraries/System.Globalization.Calendars/tests/CalendarTestWithConfigSwitch/coverage/xunit.console.runtimeconfig.json
similarity index 100%
rename from src/libraries/System.Globalization.Calendars/tests/CalendarTestWithConfigSwitch/coverage/xunit.console.netcore.runtimeconfig.json
rename to src/libraries/System.Globalization.Calendars/tests/CalendarTestWithConfigSwitch/coverage/xunit.console.runtimeconfig.json