vuln-fix: Use HTTPS instead of HTTP to resolve deps CVE-2021-26291

This fixes a security vulnerability in this project where the `pom.xml`
files were configuring Maven to resolve dependencies over HTTP instead of
HTTPS.

Weakness: CWE-829: Inclusion of Functionality from Untrusted Control Sphere
Severity: High
CVSSS: 8.1
Detection: CodeQL & OpenRewrite (https://public.moderne.io/recipes/org.openrewrite.maven.security.UseHttpsForRepositories)

Reported-by: Jonathan Leitschuh <Jonathan.Leitschuh@gmail.com>
Signed-off-by: Jonathan Leitschuh <Jonathan.Leitschuh@gmail.com>

Bug-tracker: JLLeitschuh/security-research#8

Co-authored-by: Moderne <team@moderne.io>

Author: JLLeitschuh

pom.xml

@@ -40,7 +40,7 @@
   <repositories>
     <repository>
       <id>repo.jenkins-ci.org</id>
-      <url>http://repo.jenkins-ci.org/public/</url>
+      <url>https://repo.jenkins-ci.org/public/</url>
     </repository>
   </repositories>
 
@@ -61,7 +61,7 @@
   <pluginRepositories>
     <pluginRepository>
       <id>repo.jenkins-ci.org</id>
-      <url>http://repo.jenkins-ci.org/public/</url>
+      <url>https://repo.jenkins-ci.org/public/</url>
     </pluginRepository>
   </pluginRepositories>