[Improvement] Fix potential null pointer expections in CLI

What would you like to be improved?

There are several places with potential a NPE could occur. While these are unlikely to occur, we should still add checks.

In CatalogAudit.java: displayAuditInfo(result.auditInfo());

In CreateTable.java: client.loadCatalog(catalog).asTableCatalog().createTable(tableName, columns, comment, null);

in ListCatalogProperties.java: Map<String, String> properties = gCatalog.properties();

In ListColumns.java: for (int i = 0; i < columns.length; i++) {

In ListFilesetProperties.java: Map<String, String> properties = gFileset.properties();

In ListMetalakeProperties.java: Map<String, String> properties = gMetalake.properties();

In ListSchemaProperties.java: Map<String, String> properties = gSchema.properties();

In ListTableProperties.java: Map<String, String> properties = gTable.properties();

In ListTables.java: if (tables.length == 0) {

In ListTagProperties.java: Map<String, String> properties = gTag.properties();

In ListTopicProperties.java: Map<String, String> properties = gTopic.properties();

In ModelDetails.java: String.format("Model name %s, latest version: %s%n", gModel.name(), gModel.latestVersion());

In SchemaAudit.java: displayAuditInfo(result.auditInfo());

In TableAudit.java: displayAuditInfo(gTable.auditInfo());

In TableDistribution.java: printInformation(distribution.strategy() + "," + distribution.number());

In TopicDetails.java: printResults(gTopic.name() + "," + gTopic.comment());

In UserDetails.java: if (roles.isEmpty()) {

How should we improve?

Add appropriate null checks.