fix: Add Numaflow app version in helm chart

[chandankumar4]

Fix: #15

$ helm ls -A                                                            
NAME            NAMESPACE       REVISION        UPDATED                                 STATUS          CHART           APP VERSION
numaflow        numaflow-system 1               2024-10-23 19:02:37.635594 +0530 IST    deployed        numaflow-0.0.4  1.3.3 

[vigith]

we need to write a helm-chart maintainers guide. we are bound to forget a few things, hence we need a checklist. @chandankumar4 could you please do that in a follow-up PR?