Update to 9.5.20

Changelogs:

• https://typo3.org/article/typo3-1046-and-9520-security-releases-published
• https://typo3.org/security/advisory/typo3-core-sa-2020-007
• https://typo3.org/security/advisory/typo3-core-sa-2020-008

PR: 248430
Reported by: Helmut Ritter <freebsd-ports@charlieroot.de> (maintainer)
MFH: 2020Q3
Security: eab964f8-d632-11ea-9172-4c72b94353b5
Sponsored by: Netzkommune GmbH