fix sed

Signed-off-by: Sara Damiano <sdamiano@stroudcenter.org>

.github/workflows/build_examples.yaml

@@ -85,6 +85,6 @@ jobs:
           echo "${{ env.LIBRARY_INSTALL_SOURCE }}"
           pio lib --global install ${{ env.LIBRARY_INSTALL_SOURCE }}
           pio lib --global install 89 415 1202 1286
-          sed -i 's/\/\/ #define TINY_GSM_MODEM_SIM800/#define TINY_GSM_MODEM_SIM800/'
+          sed -i 's/\/\/ #define TINY_GSM_MODEM_SIM800/#define TINY_GSM_MODEM_SIM800/g' ${{ matrix.example }}/*
           platformio ci --project-option='build_flags=-D ${{ env.TINYGSM_MODEM_TO_USE }}' --project-option='framework=arduino' --board=uno --board=leonardo --board=yun --board=megaatmega2560 --board=genuino101 --board=mkr1000USB --board=zero --board=teensy31 --board=bluepill_f103c8 --board=uno_pic32 --board=esp01 --board=nodemcuv2 --board=esp32dev
           pio lib --global uninstall TinyGSM