Merge pull request #999 from arduino/alrvid/to-lowercase-t

Changed T to t

Author: jhansson-ard

content/hardware/04.pro/boards/portenta-h7/tutorials/secure-boot/secure-boot.md

@@ -31,7 +31,7 @@ In other words, secure boot ensures that the boot technology and operating syste
 In order to have secure boot enabled, you must update the bootloader on your Portenta H7 and use [MCUboot](https://www.mcuboot.com/). You can find more info on how to perform the update in [this other tutorial](https://docs.arduino.cc/tutorials/portenta-h7/updating-the-bootloader).
 
 ### Use Default Security Keys
-Once The bootloader has been updated to MCUboot, it is possible to use [secure boot](https://www.keyfactor.com/blog/what-is-secure-boot-its-where-iot-security-starts/) to have an additional layer of security. From that point on, it is required to upload a compiled sketch with the Custom Board Option **"Security settings"** set to **"Signature + Encryption"** (the option can be found under **Tools > Security settings** in the IDE when selecting Portenta H7 as board or you can use `--board-options security=sien` if using the Arduino CLI). Failing to provide such option will cause the bootloader not to run the compiled sketch because it is not trusted.
+Once the bootloader has been updated to MCUboot, it is possible to use [secure boot](https://www.keyfactor.com/blog/what-is-secure-boot-its-where-iot-security-starts/) to have an additional layer of security. From that point on, it is required to upload a compiled sketch with the Custom Board Option **"Security settings"** set to **"Signature + Encryption"** (the option can be found under **Tools > Security settings** in the IDE when selecting Portenta H7 as board or you can use `--board-options security=sien` if using the Arduino CLI). Failing to provide such option will cause the bootloader not to run the compiled sketch because it is not trusted.
 
 If the security keys are not overridden, the default ones are used.
 Two keys are embedded in the example sketch `STM32H747_manageBootloader`, which can be found in **Files > Examples > STM32H747_System > STM32H747_manageBootloader** and used by the bootloader.