Other branch pipeline links on the pipeline header is not shown when there are backward-matched pipelines

[y-oksaku]

What happened:

Sibling pipeline link does not appear if there are many backward-matched pipelines.

Ex.
Suppose that there are pipelines based on sd-test/foo and a-sd-test/foo.
On the sd-test/foo:main pipeline, the result that search pipeline to find sibling pipeline could be the following.

a-sd-test/foo:main
a-sd-test/foo:123
a-sd-test/foo:456
...
a-sd-test/foo:789  ← Up to page 1 (default 50 rows)
...
sd-test/foo:main ← On page 2 (Not fetched)

Hence UI cannot get the sibling pipelines.

What you expected to happen:

Show the sibling pipeline link correctly.

How to reproduce it:

1. Create 50 backward-matched pipelines and create a sibling pipeline
2. Visit the pipeline landing page
3. Click branch name on the header