Update Atlassian Platform to 3.5.19 to fix CVE-2018-1000613, CVE-2019-17571 and other vulnerabilities

Update Atlassian Platform from 3.5.17 to 3.5.19. The new platform version brings changes in the following libraries:

• update com.atlassian.applinks:* from 5.4.21 to 5.4.23
• update com.atlassian.plugins:* from 4.4.10 to 4.4.14
• update com.atlassian.sal:* from 3.1.2 to 3.1.3
• update com.atlassian.streams:* from 6.3.4 to 6.3.5

Vulnerabilities fixed in Atlassian Platform 3.5.19:

• CVE-2019-17571 (removed unnecessary log4j dependency)
• CVE-2020-5398 (updated spring-web)
• CVE-2020-13956 (updated httpclient)
• CVE-2018-1000613 (removed bouncycastle dependency)