docs: Remove trailing spaces and convert tabs to spaces.

Signed-off-by: Damien George <damien@micropython.org>

docs/wipy/tutorial/reset.rst

@@ -1,10 +1,10 @@
 Reset and boot modes
 ====================
 
-There are soft resets and hard resets. 
+There are soft resets and hard resets.
 
-   - A soft reset simply clears the state of the MicroPython virtual machine, 
-     but leaves hardware peripherals unaffected. To do a soft reset, simply press 
+   - A soft reset simply clears the state of the MicroPython virtual machine,
+     but leaves hardware peripherals unaffected. To do a soft reset, simply press
      **Ctrl+D** on the REPL, or within a script do::
 
         import sys

docs/wipy/tutorial/timer.rst

@@ -5,7 +5,7 @@ Timers can be used for a great variety of tasks, calling a function periodically
 counting events, and generating a PWM signal are among the most common use cases.
 Each timer consists of two 16-bit channels and this channels can be tied together to
 form one 32-bit timer. The operating mode needs to be configured per timer, but then
-the period (or the frequency) can be independently configured on each channel. 
+the period (or the frequency) can be independently configured on each channel.
 By using the callback method, the timer event can call a Python function.
 
 Example usage to toggle an LED at a fixed frequency::

docs/wipy/tutorial/wlan.rst

@@ -13,9 +13,9 @@ You can check the current mode (which is always ``WLAN.AP`` after power up)::
 
    >>> wlan.mode()
 
-.. warning:: 
-    When you change the WLAN mode following the instructions below, your WLAN 
-    connection to the WiPy will be broken. This means you will not be able 
+.. warning::
+    When you change the WLAN mode following the instructions below, your WLAN
+    connection to the WiPy will be broken. This means you will not be able
     to run these commands interactively over the WLAN.
 
     There are two ways around this::