public Builder addEntry(Path sourceFile, AbsoluteUnixPath pathInContainer) {
      return addEntry(
          sourceFile,
          pathInContainer,
          DEFAULT_FILE_PERMISSIONS_PROVIDER.get(sourceFile, pathInContainer));
    }
Adds an entry to the layer. Only adds the single source file to the exact path in the
container file system.

<p>For example, {@code addEntry(Paths.get("myfile"),
AbsoluteUnixPath.get("/path/in/container"))} adds a file {@code myfile} to the container file
system at {@code /path/in/container}.

<p>For example, {@code addEntry(Paths.get("mydirectory"),
AbsoluteUnixPath.get("/path/in/container"))} adds a directory {@code mydirectory/} to the
container file system at {@code /path/in/container/}. This does <b>not</b> add the contents
of {@code mydirectory}.

@param sourceFile the source file to add to the layer
@param pathInContainer the path in the container file system corresponding to the {@code
    sourceFile}
@return this
jib-build-plan/src/main/java/com/google/cloud/tools/jib/api/buildplan/FileEntriesLayer.java