ci: fix coverage reporting

Author: sjinks

test/CMakeLists.txt

@@ -79,7 +79,6 @@ if(ENABLE_COVERAGE)
                 --exclude-noncode-lines --exclude-throw-branches --exclude-unreachable-branches --decisions
                 --gcov-executable="${GCOV_TOOL}"
                 --gcov-exclude-directories "${PROJECT_SOURCE_DIR}/vcpkg"
-                --gcov-delete
                 --sonarqube "${PROJECT_BINARY_DIR}/coverage/coverage-examples.xml"
         COMMAND
             gcovr -f "${PROJECT_SOURCE_DIR}/src/" -r "${PROJECT_SOURCE_DIR}"