Add jaellio as security maintainer

[jaellio]

Here are some PRs I've completed in this area (30 PRs currently merged in total):

• Add Authz test for JWT aud claim istio#50903
• Add one/many path templating support for AuthPolicy istio#50365
• Add support for DestinationRule max concurrent streams setting istio#48615
• Fix health probe port overwrite istio#45632
• Define targetRef proto api#2888
• Add istio-generated key to cacerts and create self-signed cacerts secret istio#45291
• Update Istio/SPIRE demo to use SPIRE Controller Manager istio.io#12680
• Use SPIRE Controller Manager for quickstart demo istio#43346
• Fix Custom CA Integration using K8s CSR istio#42980

Design docs/conversations:

• https://docs.google.com/document/d/1eVKo57JVQ8QGjqRkMYGHDraS_vANJf3tTUWqqbvcylQ/edit?usp=sharing
• https://docs.google.com/document/d/17L1g0LgmZP1vs-R1WJrwJvKKZwUUHIRgcDPXuTEH_qM/edit#heading=h.xw1gqgyqs5b
• Support regex for ServiceRole spec.rules.paths istio#16585 (comment)

I want to join the Istio org!

• I have reviewed the community membership guidelines
• I have reviewed the contribution guidelines
• I have enabled 2FA on my GitHub account
• I have joined Istio's Slack workspace
• I have written my company name or "Individual", if not affliated with a company, here: Microsoft
• I have provided a link to at least one PR that I have successfully pushed to one of the Istio repos, here: 30 PRs Merged

[howardjohn]

This LGTM personally. Thanks for all the contributions!

FWIW @jaellio is already on the PSWG so this is just a slight expansion of responsibilities, not a first time maintainer`

[kfaseela]

Congratulations @jaellio

[linsun]

Congrats @jaellio - LGTM too!

[justinpettit]

Congratulations, @jaellio!