code: public DockerRuleBuilder link(DockerRule targetContainer, String alias) {
          LinkNameValidator.validateContainerName(alias);
          dynamicLinks.add(Pair.of(targetContainer, alias));
          return this;
      }
docs: Dynamic link.
  Define (legacy) container links (equaivalent of command-line <code>--link "targetContainerId:alias"</code>
  where targetContainerId will be substituted after target container start).
  Legacy links works only on docker <code>bridge</code> network.
  <p>
  Unlike static link (see {@link #link(String)}) it does not require assigning name to target container
  so it is especially convenient in setups where multiple concurrent test cases
  shares single docker server.
  <p>
  Target container must be started first and <b>because of no guarantees of rule execution
  order in JUnit suggested solution is to take advantage of JUnit {@link RuleChain}</b>, for example:
  <pre>
  DockerRule db = DockerRule.builder()
  .imageName("busybox")
  ...
  
  DockerRule web = DockerRule.builder()
  .imageName("busybox")
  .link(db, "db")
  ...
  
  {@literal @}Rule
  public RuleChain containers = RuleChain.outerRule(db).around(web);
  
  </pre>
  
  @param targetContainer Container link points to
  @param alias Alias assinged to link in current container