minor #32944 [Yaml] Removed unused $nullAsTilde property (pierredup)
minor #32944 [Yaml] Removed unused $nullAsTilde property (pierredup)

This PR was squashed before being merged into the 4.4 branch (closes #32944).

Discussion
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[Yaml] Removed unused $nullAsTilde property

| Q             | A
| ------------- | ---
| Branch?       | 4.4
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | N/A
| License       | MIT
| Doc PR        | N/A

#32669 added a new private property `$nullAsTilde`, but that property was never used, so this PR removes the unused property

Commits
-------

fbef8543cd [Yaml] Removed unused $nullAsTilde property

mnapoli/symfony,Nyholm/symfony,mpdude/symfony,gonzalovilaseca/symfony,sgehrig/symfony,bendavies/symfony,oleg-andreyev/symfony,bendavies/symfony,jvasseur/symfony,phramz/symfony,Taluu/symfony,tucksaun/symfony,kbond/symfony,localheinz/symfony,shieldo/symfony,chalasr/symfony,mpdude/symfony,nicolas-grekas/symfony,oleg-andreyev/symfony,dmaicher/symfony,voronkovich/symfony,docteurklein/symfony,dmaicher/symfony,1ed/symfony,chalasr/symfony,alekitto/symfony,shieldo/symfony,docteurklein/symfony,romaricdrigon/symfony,tucksaun/symfony,nicolas-grekas/symfony,derrabus/symfony,d-ph/symfony,fabpot/symfony,symfony/symfony,stof/symfony,jvasseur/symfony,smatyas/symfony,ro0NL/symfony,ragboyjr/symfony,ro0NL/symfony,zcodes/symfony,Slamdunk/symfony,tgalopin/symfony,kbond/symfony,Deamon/symfony,docteurklein/symfony,MatTheCat/symfony,symfony/symfony,ogizanagi/symfony,symfony/symfony,pierredup/symfony,damienalexandre/symfony,damienalexandre/symfony,localheinz/symfony,romaricdrigon/symfony,Tobion/symfony,shieldo/symfony,fabpot/symfony,mweimerskirch/symfony,hhamon/symfony,pyrech/symfony,mnapoli/symfony,damienalexandre/symfony,fabpot/symfony,zorn-v/symfony,xabbuh/symfony,Simperfit/symfony,stof/symfony,zerkms/symfony,stof/symfony,Slamdunk/symfony,d-ph/symfony,ogizanagi/symfony,smatyas/symfony,voronkovich/symfony,Nyholm/symfony,mnapoli/symfony,lstrojny/symfony,ogizanagi/symfony,zerkms/symfony,alekitto/symfony,ragboyjr/symfony,HeahDude/symfony,Koc/symfony,kbond/symfony,pyrech/symfony,zerkms/symfony,MatTheCat/symfony,lyrixx/symfony,OskarStark/symfony,yceruto/symfony,xabbuh/symfony,derrabus/symfony,Taluu/symfony,docteurklein/symfony,Simperfit/symfony,oleg-andreyev/symfony,derrabus/symfony,hhamon/symfony,OskarStark/symfony,sgehrig/symfony,Taluu/symfony,jderusse/symfony,tgalopin/symfony,paradajozsef/symfony,stof/symfony,localheinz/symfony,Simperfit/symfony,mweimerskirch/symfony,Deamon/symfony,paradajozsef/symfony,yceruto/symfony,alekitto/symfony,sgehrig/symfony,smatyas/symfony,romaricdrigon/symfony,symfony/symfony,tgalopin/symfony,pierredup/symfony,lyrixx/symfony,mpdude/symfony,jderusse/symfony,xabbuh/symfony,garak/symfony,1ed/symfony,OskarStark/symfony,tucksaun/symfony,paradajozsef/symfony,mnapoli/symfony,fabpot/symfony,Koc/symfony,Nyholm/symfony,Deamon/symfony,phramz/symfony,localheinz/symfony,Simperfit/symfony,hhamon/symfony,oleg-andreyev/symfony,hhamon/symfony,jakzal/symfony,d-ph/symfony,lstrojny/symfony,mnapoli/symfony,1ed/symfony,nicolas-grekas/symfony,Tobion/symfony,xabbuh/symfony,smatyas/symfony,gonzalovilaseca/symfony,jakzal/symfony,jakzal/symfony,Nyholm/symfony,Tobion/symfony,mpdude/symfony,zcodes/symfony,maidmaid/symfony,d-ph/symfony,jvasseur/symfony,damienalexandre/symfony,dmaicher/symfony,zorn-v/symfony,sgehrig/symfony,pyrech/symfony,mweimerskirch/symfony,tucksaun/symfony,smatyas/symfony,dmaicher/symfony,ragboyjr/symfony,zorn-v/symfony,garak/symfony,MatTheCat/symfony,mweimerskirch/symfony,shieldo/symfony,lyrixx/symfony,docteurklein/symfony,pierredup/symfony,chalasr/symfony,mweimerskirch/symfony,Koc/symfony,jderusse/symfony,pierredup/symfony,pyrech/symfony,voronkovich/symfony,maidmaid/symfony,lstrojny/symfony,gonzalovilaseca/symfony,garak/symfony,yceruto/symfony,gonzalovilaseca/symfony,bendavies/symfony,curry684/symfony,derrabus/symfony,kbond/symfony,ro0NL/symfony,voronkovich/symfony,maidmaid/symfony,Simperfit/symfony,curry684/symfony,Tobion/symfony,ragboyjr/symfony,ro0NL/symfony,paradajozsef/symfony,Deamon/symfony,curry684/symfony,Koc/symfony,Slamdunk/symfony,jvasseur/symfony,jakzal/symfony,lyrixx/symfony,chalasr/symfony,bendavies/symfony,ogizanagi/symfony,Slamdunk/symfony,Deamon/symfony,curry684/symfony,zorn-v/symfony,Taluu/symfony,HeahDude/symfony,phramz/symfony,romaricdrigon/symfony,tgalopin/symfony,jderusse/symfony,1ed/symfony,maidmaid/symfony,phramz/symfony,yceruto/symfony,HeahDude/symfony,nicolas-grekas/symfony,MatTheCat/symfony,OskarStark/symfony,HeahDude/symfony,zcodes/symfony,alekitto/symfony,garak/symfony,zcodes/symfony,zerkms/symfony