doc: conf.py: Replace bare 'except' with 'except Exception'
doc: conf.py: Replace bare 'except' with 'except Exception'

A bare 'except:' can do some annoying stuff like eat Ctrl-C (because it
catches KeyboardInterrupt). Better to use 'except Exception:' as a
catch-all.

Even better might be to catch some more specific exception, because even
'except Exception:' eats stuff like misspelled identifiers.

Fixes this pylint warning:

    doc/conf.py:99:0: W0702: No exception type(s) specified
    (bare-except)

Signed-off-by: Ulf Magnusson <01743f1c1deb1fe75271d62edb65757d98ac0bcb@nordicsemi.no>

Vudentz/zephyr,zephyrproject-rtos/zephyr,nashif/zephyr,nashif/zephyr,finikorg/zephyr,galak/zephyr,nashif/zephyr,finikorg/zephyr,Vudentz/zephyr,zephyrproject-rtos/zephyr,Vudentz/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,Vudentz/zephyr,Vudentz/zephyr,galak/zephyr,Vudentz/zephyr,finikorg/zephyr,finikorg/zephyr,nashif/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,galak/zephyr,finikorg/zephyr,nashif/zephyr,galak/zephyr