add optional api-server prefix

[yehiyam]

This change is 

[nassiharel]

Reviewed 1 of 2 files at r1.
Reviewable status: 1 of 2 files reviewed, 1 unresolved discussion (waiting on @yehiyam)

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core/api-server/config/main/config.base.js, line 56 at r1 (raw file):

 path: process.env.BASE_URL_PATH? path.join(config.ingressPrefix, process.env.BASE_URL_PATH): config.ingressPrefix

Writing this is the same?
path: path.join(config.ingressPrefix, process.env.BASE_URL_PATH || '')

[yehiyam]

Reviewable status: 1 of 3 files reviewed, 1 unresolved discussion (waiting on @nassiharel)

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core/api-server/config/main/config.base.js, line 56 at r1 (raw file):

Previously, NassiHarel (Nassi Harel) wrote…

 path: process.env.BASE_URL_PATH? path.join(config.ingressPrefix, process.env.BASE_URL_PATH): config.ingressPrefix

Writing this is the same?
path: path.join(config.ingressPrefix, process.env.BASE_URL_PATH || '')

if both ingressPath and BASE_URL are empty your option returns . and not empty string. Added tests to verify

[nassiharel]

Reviewed 1 of 2 files at r1, 1 of 1 files at r2.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @yehiyam)

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core/api-server/config/main/config.base.js, line 56 at r1 (raw file):

 path.join

Yes
"If the joined path string is a zero-length string then '.' will be returned, representing the current working directory."

https://nodejs.org/api/path.html#path_path_join_paths

[yehiyam]

Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @nassiharel)

---

core/api-server/config/main/config.base.js, line 56 at r1 (raw file):

Previously, NassiHarel (Nassi Harel) wrote…

 path.join

Yes
"If the joined path string is a zero-length string then '.' will be returned, representing the current working directory."

https://nodejs.org/api/path.html#path_path_join_paths

Done.