Open tutorial file using normal mode

[dstrain115]

• The option 'r|xz' opens an lzma compressed stream for reading.
• This causes a StreamError: "seeking backwards is not allowed".
• This changes it to 'r:xz' which opens it as a normal file so it is seekable.
• This fixes a problem with rendering the documentation for reCirq

[mhucka]

This is peculiar. When I run pytest recirq/documentation_utils_test.py on MacOS under Python 3.11, it passes, yet it does contain a test that invokes fetch_guide_data_collection_data. The test is evidently insufficient. @dstrain115 How did you get the stream error? We should improve the test.

[dstrain115]

This is peculiar. When I run pytest recirq/documentation_utils_test.py on MacOS under Python 3.11, it passes, yet it does contain a test that invokes fetch_guide_data_collection_data. The test is evidently insufficient. @dstrain115 How did you get the stream error? We should improve the test.

The function fetch_guide_data_collection_data downloads data from the internet, so the test patches @mock.patch('urllib.request.urlopen') so somehow this error doesn't manifest then.

I ran it in a colab.

[mhucka]

It check and it works with either way (using : or |) from a command-line invocation. Since it works in more places (apparently) with :, this change is certainly worth making.

Thanks for finding & fixing this!

[mhucka]

LGTM