[chore][CI/CD] Fix github action for pinging code owners on some components

[crobert-1]

Description:

Existing bug:
This resolves a bug in pinging code owners that was hit when a base component doesn't end with its type, but has multiple sub-components.

For example, when adding the label extension/encoding to issues code owners weren't being pinged. This is because there are multiple sub-components (e.g. extension/encoding/jaegarencodingextension, extension/encoding/zipkinencodingextension, etc), and extension/encoding doesn't end with its own type extension.

Solution:
The solution to this bug is to also check if the original component can be found if a single / is appended to it. This finds the component in a determinate way and allows code owners to be pinged properly.

Link to tracking Issue:

Resolves #29571

Testing:

crobert$ ~/dev/opentelemetry-collector-contrib $ export COMPONENT=extension/encoding
crobert$ ~/dev/opentelemetry-collector-contrib $ .github/workflows/scripts/get-codeowners.sh 
@atoulme @dao-jun @dmitryax @MovieStoreGuy @VihasMakwana
crobert$ ~/dev/opentelemetry-collector-contrib $ export COMPONENT=extension/encoding/zipkinencoding
crobert$ ~/dev/opentelemetry-collector-contrib $ .github/workflows/scripts/get-codeowners.sh 
@MovieStoreGuy @dao-jun
crobert$ ~/dev/opentelemetry-collector-contrib $ export COMPONENT=processor/resourcedetection
crobert$ ~/dev/opentelemetry-collector-contrib $ .github/workflows/scripts/get-codeowners.sh 
@Aneurysm9 @dashpole
crobert$ ~/dev/opentelemetry-collector-contrib $ export COMPONENT=extension/observer
crobert$ ~/dev/opentelemetry-collector-contrib $ .github/workflows/scripts/get-codeowners.sh
@dmitryax @rmfitzpatrick
crobert$ ~/dev/opentelemetry-collector-contrib $ export COMPONENT=processor/resource
crobert$ ~/dev/opentelemetry-collector-contrib $ .github/workflows/scripts/get-codeowners.sh
@dmitryax

Previously, extension/observer and extension/encoding returned nothing, which was the bug this resolves.

[crobert-1]

This is the exact same logic as before, just using the argument passed to the function instead of a global variable.

[crobert-1]

Existing code structure should be the same as before, just a single condition is added. Originally there was a single statement setting OWNERS because COMPONENT was modified to have the COMPONENT_TYPE appended to it.

So even though there's an if/else condition here now, it's the same logic, just an extra condition for the / appended instead of COMPONENT_TYPE.

[crobert-1]

If we want to really ensure this worked, we can add labels to this PR to make sure code owners are pinged. It would be noisy for them, but probably better than merging if I somehow broke something. Otherwise I can test on an issue this is broken for after its merged.

[atoulme]

Let's try it with one component and see if it works.

[atoulme]

It doesn't I guess since it applies the script from main, so we need to merge this to see if it works.

[evan-bradley]

Really appreciate you taking a look at this.