ci: allow nonexistent profile in google-cloud-bigtable

Our release job specifies profiles that may or may not exist in
all Java projects in our release pipeline. The
requireProfileIdsExist enforcer rule fails in that case.

Therefore, let's remove the requireProfileIdsExist rule.

Author: suztomo

google-cloud-bigtable/pom.xml

@@ -673,18 +673,6 @@
         <artifactId>maven-enforcer-plugin</artifactId>
         <version>3.5.0</version>
         <executions>
-          <!-- Prevent users from mistyping a profile name -->
-          <execution>
-            <id>enforce-valid-profile</id>
-            <configuration>
-              <rules>
-                <requireProfileIdsExist/>
-              </rules>
-            </configuration>
-            <goals>
-              <goal>enforce</goal>
-            </goals>
-          </execution>
           <!-- Ensure that greatest version of each transitive dependency got selected -->
           <execution>
             <id>enforce-dependency-upper-bound</id>