[pulsar-broker] validate namespace isolation policy regex before updating

[rdhabalia]

Motivation

Right now, the broker stores ns-isolation policy regex without validating which will cause failure at runtime. So, perform fast fail validation and validate policy before storing instead of failing at runtime with invalid policy regex.

23:14:56.710 [pulsar-1-11] WARN  o.a.p.b.l.i.SimpleResourceAllocationPolicies - isPrimaryForAnyNamespace: [{}]
java.util.regex.PatternSyntaxException: Illegal character range near index 16
test-broker1[45-46].uswest.com.*
                 ^
        at java.util.regex.Pattern.error(Pattern.java:1955) ~[na:1.8.0_131]
        at java.util.regex.Pattern.range(Pattern.java:2655) ~[na:1.8.0_131]
        at java.util.regex.Pattern.clazz(Pattern.java:2562) ~[na:1.8.0_131]
        at java.util.regex.Pattern.sequence(Pattern.java:2063) ~[na:1.8.0_131]
        at java.util.regex.Pattern.expr(Pattern.java:1996) ~[na:1.8.0_131]
        at java.util.regex.Pattern.compile(Pattern.java:1696) ~[na:1.8.0_131]
        at java.util.regex.Pattern.<init>(Pattern.java:1351) ~[na:1.8.0_131]
        at java.util.regex.Pattern.compile(Pattern.java:1028) ~[na:1.8.0_131]
        at java.util.regex.Pattern.matches(Pattern.java:1133) ~[na:1.8.0_131]
        at java.lang.String.matches(String.java:2121) ~[na:1.8.0_131]
        at org.apache.pulsar.common.policies.impl.NamespaceIsolationPolicyImpl.matchesBrokerRegex(NamespaceIsolationPolicyImpl.java:104)

[rdhabalia]

/pulsarbot run-failure-checks

[rdhabalia]

/pulsarbot run-failure-checks

[zymap]

The test is failed by this.

Error:  testBookKeeperDown(org.apache.pulsar.tests.integration.cli.HealthCheckTest)  Time elapsed: 0.194 s  <<< FAILURE!
org.apache.pulsar.tests.integration.docker.ContainerExecException: pkill -STOP -f BookieServer failed on e3f20778f4944a0efbec3d50a936bc48e8d43e87f0bfe514dd6e80be937546ec with error code 1
	at org.apache.pulsar.tests.integration.utils.DockerUtils$2.onComplete(DockerUtils.java:259)
	at com.github.dockerjava.core.exec.AbstrAsyncDockerCmdExec$1.onComplete(AbstrAsyncDockerCmdExec.java:51)
	at com.github.dockerjava.okhttp.OkHttpInvocationBuilder.lambda$executeAndStream$4(OkHttpInvocationBuilder.java:331)
	at java.lang.Thread.run(Thread.java:748)

I remember it already fixed in PR #8791. So could you please rebase to the latest master?

[rdhabalia]

/pulsarbot run-failure-checks