toolchains: Add recommended toolchain flags (#110)

* toolchains: Add recommended toolchain flags

Recommended toolchain flags are added to both
GNU and ARMClang toolchains.

Signed-off-by: Ahmed Ismail <Ahmed.Ismail@arm.com>

* formatting: Update the job to run on Ubuntu 22.04

Ubuntu 20.04 LTS runner will be removed mid April
2025. Hence, updating to use Ubuntu 22.04.

Signed-off-by: Ahmed Ismail <Ahmed.Ismail@arm.com>

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Signed-off-by: Ahmed Ismail <Ahmed.Ismail@arm.com>