fix(scraper): issue on video size, reproduce the bug

[vvatelot]

Following #58, it seems that on certain analysis the result is wrong with video resources. When using haralyzer, we can confirm that on a given page the results from the har analysis seems to be wrong:

https://www.graphic-sud.com/
         type  count_ecoindex  size_ecoindex  count_haralyzer  size_haralyzer
0       audio               0          0.000              0.0           0.000
1         css               5         24.403              5.0          24.403
2        font               2         72.424              NaN             NaN
3        html               1         30.474              1.0             NaN
4       image               8        585.199              8.0         585.199
5  javascript               7         84.564              7.0          84.564
6       other               0          0.000              6.0          54.877
7       video               2      15317.080              2.0          56.414
8       total              25      16114.144             25.0         853.478

Proposition:

• Use haralyzer to extracts metrics instead of custom development
• Update documentation of ecoindex website to explain that we simulate a keystroke arrow down during the analysis

[github-actions]

Branch coverage •

File	Stmts	Miss	Cover	Missing
components/ecoindex/scraper
scrap.py	91	51	43%	45, 48–49, 51, 60, 63, 66–68, 73–75, 77–81, 84–87, 89, 91, 98–101, 108–110, 112–121, 130–131, 134–135, 137, 146–147, 152–153, 157–158
TOTAL	695	230	66%

[PaulPHPE]

Hello @vvatelot !

This difference between the two results is due to the fact that when we have a _transferSize = -1 then we opt to retrieve the content-length of the response, a step not performed by haranalyzer.
This enables us to take into account video and audio requests. However, we do not differentiate between videos in autoplay mode and those with autoplay disabled.

In response, I propose the following for the PR:
By default, refrain from retrieving the content-length. If _transferSize = -1, set size = 0.
Then, verify if the video is set to autoplay. If affirmative, obtain the value of the content-length. However, implementing this may pose challenges as it requires parsing the HTML to locate the autoplay option.