feat: allow to download results from all pages

[anesson-cs]

Fixes #133

After searching some products, we can now download the ones from all pages of this search by setting exhaust to True in download_all() method parameters.

It works by saving some elements in several objects:

• search params in SearchResults object to search next pages of the search
• list of crunchers in SearchResults object to apply them on next pages and to skip a crunch if it has already been applied on the object
• list of search params in EODataAccessGateway object to skip a page when it has already been requested

Then, the search_iter_page() is called to search products from all pages by skipping the one already found.
Finally, if there are other products, they are added to the initial SearchResults object.

• Add units tests

[github-actions]

Test Results

       4 files  ±0         4 suites  ±0   5m 44s ⏱️ -16s
   401 tests ±0     399 ✔️ ±0    2 💤 ±0  0 ❌ ±0 
1 604 runs  ±0  1 544 ✔️ ±0  60 💤 ±0  0 ❌ ±0 

Results for commit 480239a. ± Comparison against base commit f2ac36b.

[github-actions]

Code Coverage (Ubuntu)

File	Coverage
All files	81%	✅

Minimum allowed coverage is 70%

Generated by 🐒 cobertura-action against 480239a

[github-actions]

Code Coverage (Windows)

File	Coverage
All files	76%	✅

Minimum allowed coverage is 70%

Generated by 🐒 cobertura-action against 480239a