Fix TypeError in oracle/networking/lbNoInstances.js

[ByteMeShiv]

Bug

The lbNoInstances plugin throws an uncaught TypeError when scanning a load balancer that has backend instances actually attached, causing the entire Oracle scan to crash and exit non-zero (no report is generated when this happens).

node --max-old-space-size=8192 ./index.js --json=<file> --config ./cloudsploit_oci_config.js --console=none

/app/cloudsploit/plugins/oracle/networking/lbNoInstances.js:50
    helpers.addResult(results, 0, 'LB has ' + lb[lb.displayName].backends.length + ' backend instances', region, lb.id);
                                                                                    ^

TypeError: Cannot read properties of undefined (reading 'backends')
    at /app/cloudsploit/plugins/oracle/networking/lbNoInstances.js:50:90
    at /app/cloudsploit/node_modules/async/dist/async.js:3113:16
    at eachOfArrayLike (/app/cloudsploit/node_modules/async/dist/async.js:1072:9)
    at eachOf (/app/cloudsploit/node_modules/async/dist/async.js:1120:5)
    at Object.eachLimit (/app/cloudsploit/node_modules/async/dist/async.js:3175:5)
    at /app/cloudsploit/plugins/oracle/networking/lbNoInstances.js:42:23
    at /app/cloudsploit/node_modules/async/dist/async.js:3113:16
    at eachOfArrayLike (/app/cloudsploit/node_modules/async/dist/async.js:1072:9)
    at eachOf (/app/cloudsploit/node_modules/async/dist/async.js:1120:5)
    at Object.eachLimit (/app/cloudsploit/node_modules/async/dist/async.js:3175:5)

Root cause

The if guard correctly validates lbBackend (lb.backendSets['bs_' + lb.displayName]), but the success-branch message builder reads from a different, unrelated, and unvalidated property instead:

var lbBackend = lb.backendSets['bs_' + lb.displayName];
if (lbBackend && lbBackend.backends && lbBackend.backends.length) {
    helpers.addResult(results, 0, 'LB has ' + lb[lb.displayName].backends.length + ' backend instances', region, lb.id);
    //