Additional factory methods

These factory methods are identical to the ones already existing in
metrics/CircuitBreakerMetrics.java. Their purpose is to allow
Spring Boot applications to instantiate CircuitBreakerMetrics and
have fine-grained control over which circuit breakers are bound to
metrics, in particular in scenarios where the CircuitBreakerRegistry
may not be completely populated by the time the CircuitBreakerMetrics
class is instantiated.

resilience4j-micrometer/src/main/java/io/github/resilience4j/micrometer/CircuitBreakerMetrics.java

@@ -49,6 +49,26 @@ public static CircuitBreakerMetrics ofCircuitBreakerRegistry(CircuitBreakerRegis
         return new CircuitBreakerMetrics(circuitBreakerRegistry.getAllCircuitBreakers());
     }
 
+    /**
+     * Creates a new instance CircuitBreakerMetrics {@link CircuitBreakerMetrics} with
+     * an {@link Iterable} of circuit breakers as a source.
+     *
+     * @param circuitBreakers the circuit breakers
+     */
+    public static CircuitBreakerMetrics ofIterable(Iterable<CircuitBreaker> circuitBreakers) {
+        return new CircuitBreakerMetrics(circuitBreakers);
+    }
+
+    /**
+     * Creates a new instance CircuitBreakerMetrics {@link CircuitBreakerMetrics} with
+     * an {@link Iterable} of circuit breakers as a source.
+     *
+     * @param circuitBreakers the circuit breakers
+     */
+    public static CircuitBreakerMetrics ofIterable(String prefix, Iterable<CircuitBreaker> circuitBreakers) {
+        return new CircuitBreakerMetrics(circuitBreakers, prefix);
+    }
+
     @Override
     public void bindTo(MeterRegistry registry) {
         for (CircuitBreaker circuitBreaker : circuitBreakers) {