Remove okhttp3 okhttp-urlconnection for 3.14.x release

The urlconnection has not been support for many years and is incompatible with
a number of okhttp3 features.  Better to not include it.

See https://square.github.io/okhttp/changelog_3x/#version-3140 and copy down the
ObsoleteUrlFactory if you absolutely must, but we do not want to have this plugin forcing that dependency.

pom.xml

@@ -23,13 +23,13 @@
   <url>https://github.com/jenkinsci/okhttp-api-plugin</url>
 
   <properties>
-    <revision>3.12.12.2</revision>
+    <revision>3.14.9</revision>
     <changelist>-SNAPSHOT</changelist>
     <jenkins.version>2.164.3</jenkins.version>
     <java.level>8</java.level>
     <no-test-jar>false</no-test-jar>
     <okhttp.version>2.7.5</okhttp.version>
-    <okhttp3.version>3.12.12</okhttp3.version>
+    <okhttp3.version>3.14.9</okhttp3.version>
     <okio.version>1.17.5</okio.version>
   </properties>
 
@@ -45,11 +45,6 @@
       <artifactId>okhttp</artifactId>
       <version>${okhttp3.version}</version>
     </dependency>
-    <dependency>
-      <groupId>com.squareup.okhttp3</groupId>
-      <artifactId>okhttp-urlconnection</artifactId>
-      <version>${okhttp3.version}</version>
-    </dependency>
     <dependency>
       <groupId>com.squareup.okhttp</groupId>
       <artifactId>okhttp</artifactId>