Add/fix ReadTheDocs badge

[tannewt]

We had a bad cookiecutter for a while that added extra lines into the README.rst in the ReadTheDocs badge like this:

.. image:: https://readthedocs.org/projects/adafruit-circuitpython-vcnl4010/badge/?version=latest

    :target: https://circuitpython.readthedocs.io/projects/vcnl4010/en/latest/

    :alt: Documentation Status

It should be:

.. image:: https://readthedocs.org/projects/adafruit-circuitpython-vcnl4010/badge/?version=latest
    :target: https://circuitpython.readthedocs.io/projects/vcnl4010/en/latest/
    :alt: Documentation Status

These are super simple changes that are great practice for using GitHub. Feel free to ask questions here as needed.

These repos need a look:

• https://github.com/adafruit/Adafruit_CircuitPython_VCNL4010
• https://github.com/adafruit/Adafruit_CircuitPython_Fingerprint
• https://github.com/adafruit/Adafruit_CircuitPython_APDS9960
• https://github.com/adafruit/Adafruit_CircuitPython_DRV2605
• https://github.com/adafruit/Adafruit_CircuitPython_SGP30
• https://github.com/adafruit/Adafruit_CircuitPython_DS18X20
• https://github.com/adafruit/Adafruit_CircuitPython_AVRprog
• https://github.com/adafruit/Adafruit_CircuitPython_FocalTouch
• https://github.com/adafruit/Adafruit_CircuitPython_MCP9808
• https://github.com/adafruit/Adafruit_CircuitPython_VL6180X
• https://github.com/adafruit/Adafruit_CircuitPython_OneWire
• https://github.com/adafruit/Adafruit_CircuitPython_Thermal_Printer
• https://github.com/adafruit/Adafruit_CircuitPython_DS2413
• https://github.com/adafruit/Adafruit_CircuitPython_VEML6070
• https://github.com/adafruit/Adafruit_CircuitPython_MAX9744
• https://github.com/adafruit/Adafruit_CircuitPython_MCP4725
• https://github.com/adafruit/Adafruit_CircuitPython_SSD1306
• https://github.com/adafruit/Adafruit_CircuitPython_SHT31D
• https://github.com/adafruit/Adafruit_CircuitPython_TLC5947
• https://github.com/adafruit/Adafruit_CircuitPython_Register

Part of #566

[brentru]

@tannewt I noticed the SSD1306 repo 404's on its ReadTheDocs page. Is there another ReadTheDocs page, or a correct link to this badge?

Also - the register library doesn't seem to follow the default badge URL path, is there a correct URL for this?

[tannewt]

Thats the right link for ssd1306 but the build itself isn't set up right. The build output is here: https://readthedocs.org/projects/adafruit-circuitpython-ssd1306/builds/6661205/

I'd expect register to be at https://circuitpython.readthedocs.io/projects/register/en/latest/

[mrmcwethy]

@ tannewt @brentru I believe this issue can now be closed.

[tannewt]

Great job @mrmcwethy and @brentru !