Fix some images reading when some operations are inserted between EI and Q
end of image is now considered with [whitespace]EI[whitespace] (4 characters should be sufficient)

Fixes #1090

Fixes #1329

* Prevent loop within dictionaries caused by objects not respecting the PDF standard
* Fix cmap warnings due to "numbered" characters ( #2d instead of -)
* Apply unnumbering to NameObject
* Add _get_indirect_object for debugging and development
* Add some missing seeks (no issue reported yet)

Robustness (ROB):
-  Fix infinite loop due to Invalid object (#1331)
-  Fix image extraction issue with superfluous whitespaces (#1327)

Full Changelog: 2.10.5...2.10.6

…1325)

Replace the warning-as-exception checks with use of `pytest.warns()`.

That is more semantically correct and works correctly when the tests
are run without -Werror (e.g. because -Werror tends to cause test suites
to crash on irrelevant deprecation warnings from other components).

While at it, replace the homegrown exception checks in test_orientations
with `pytest.raises()`.

Fixes #1340

Error detected during analysis of #1280

Bug Fixes (BUG):
-  Fix Error in transformations (#1341)
-  Decode #23 in NameObject (#1342)

Testing (TST):
-  Use pytest.warns() for warnings, and .raises() for exceptions (#1325)

Full Changelog: 2.10.6...2.10.7

Three kinds of changes were made in this PR

1) _cmap.py : the str is coming from `/Encoding` which stores a NameObject : The conversion is already performed; no need to force it.
2) _page.py : Replaced obsolete call in _debug_for_extract()
3) _base.py :
3.1) unnumber : all `#xx` should be performed prior to conversion to str (using utf-8) to allow multi language text
3.2) read_from_stream : if utf-8 (normally the only one required) or gbk (kept to prevent regression) we will use charmap to get some sequence of chars
3.3) renumber : added to recode in #xx sequence. renumber will also be compatible with utf-8 chars

Closes #1344

Co-authored-by: Matthew Peveler <matt.peveler@gmail.com>

New Features (ENH):
-  Add PageObject.user_unit property (#1336)

Robustness (ROB):
-  Improve NameObject reading/writing (#1345)

Full Changelog: 2.10.7...2.10.8