Fix some security audits dates format (cncf#3418)

Signed-off-by: Cintia Sanchez Garcia <cynthiasg@icloud.com>
Signed-off-by: Lars Larsson <lars.larsson@elastisys.com>

landscape.yml

@@ -3290,11 +3290,11 @@ landscape:
               youtube_url: https://www.youtube.com/channel/UCZ2bu0qutTOM0tHYa_jkIwg
               clomonitor_name: kubernetes
               audits:
-                - date: 20190806
+                - date: '2019-08-06'
                   type: security
                   url: https://github.com/kubernetes/sig-security/tree/main/sig-security-external-audit/security-audit-2019/findings
                   vendor: Trail of Bits and Atredis Partners
-                - date: 20230419
+                - date: '2023-04-19'
                   type: security
                   url: https://github.com/kubernetes/sig-security/tree/main/sig-security-external-audit/security-audit-2021-2022/findings
                   vebdor: NCC Group
@@ -9287,7 +9287,7 @@ landscape:
               summary_intro_url: ''
               clomonitor_name: jaeger
               audits:
-                - date: '2019--05-04'
+                - date: '2019-05-04'
                   type: security
                   url: https://github.com/jaegertracing/security-audits/blob/master/SECURITY_AUDIT_2019_05_04.pdf
                   vendor: Cure53