Upgrade EasyRdf to version 1.1.*

[osma]

This PR upgrades EasyRdf to version 1.1.* (currently 1.1.1)
The only Skosmos code change, apart from changing the dependency, was to change two fields in SkosmosTurtleParser from private to protected, to avoid compiler errors.

Upgrading is required to make progress on issue #920 / PR #1127, since the old EasyRdf version we were using is not compatible with PHP 7.4.

[osma]

Hmm, I think that actually SkosmosTurtleParser could now be simplified, since the changes to make the parser more efficient were merged into EasyRdf long ago and they are now in the 1.1.1 version we are upgrading to...

[sonarcloud]

Kudos, SonarCloud Quality Gate passed!

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

No Coverage information
No Duplication information

[codecov]

Codecov Report

Merging #1128 (1720e43) into master (6a01b70) will increase coverage by 0.09%.
The diff coverage is n/a.

@@             Coverage Diff              @@
##             master    #1128      +/-   ##
============================================
+ Coverage     60.30%   60.39%   +0.09%     
+ Complexity     1600     1583      -17     
============================================
  Files            32       32              
  Lines          4436     4376      -60     
============================================
- Hits           2675     2643      -32     
+ Misses         1761     1733      -28     

Impacted Files	Coverage Δ	Complexity Δ
model/SkosmosTurtleParser.php	100.00% <ø> (+45.16%)	1.00 <0.00> (-17.00)	⬆️

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[kouralex]

Perfect! It is a bit sad that we still need SkosmosTurtleParser as the parsed namespaces are not public. The only way I can think of is to save a reference to the parser object itself in GlobalConfig and call it directly but I guess that does not make much sense..

Anyways, will gladly merge! Very nice upgrade and needed, indeed! :)