chore(sprig): bump sprig to 2.15.0

The defined role does not allow Tiller to launch Kubernetes jobs

Update CONTRIBUTING.md

This change updates sprig to 2.15, which has support for generating
SSL certificates in charts from user defined CA certificates.

Migrate 'template' to 'include' in 'helm create' 

docs(release_checklist): Adds information about new release meetings

chore(docs): mv index.md to README.md

add SECURITY_CONTACTS

Fix(helm): fix the bug of the charts not deployed after downloaded in helm install --dep-up

in helm install --dep-up

helm install --dep-up does not deploy the charts downloaded by itself.
I reload the charts path after downloading the missing charts.

Closes #3423

typo fix for template test

Suppress 'unauthenticated users' warning when --tiller-tls-verify present

feat(list): Optional output as JSON and YAML

fix charts doc: there shouldn't be a space in between the conditions

Fix inaccurate comment in `tiller`

Merge pull request #4135 from mattjmcnaughton/mattjmcnaughton/4086-fix-concurrency-issues-with-helm-install

Fix concurrency issues with helm install

Make --set-string flag parse booleans and null as strings

Setting DisableCompression to true to disable unwanted httpclient transformation

Merge pull request #4176 from mattjmcnaughton/mattjmcnaughton/4174-more-specific-name-reuse-error-message

Increase error message specificity for name reuse

test(helm): add test for 'ParseIntoString' and update test for 'ParseInto'

Remove trailing whitespace from Charts documentation

Add s390 architecture in TARGETS

typo fix for lengh to length

Signed-off-by: Alice Frosi <alice@linux.vnet.ibm.com>

Documentation formatting [Tiny]

Typo fix: indentifies -> identifies

If `helm upgrade` fails because a reused name is still in use, the error
message does not specify which name is still in use. Update the error
message.

Add link to cdwv/awesome-helm

Added documentation for the tpl function

Typo fix: retruns->returns

retruns->returns