Add migration from GitBucket (#16767)

This PR adds [GitBucket](https://gitbucket.github.io/) as migration source.

Supported:
- Milestones
- Issues
- Pull Requests
- Comments
- Reviews
- Labels

There is no public usable instance so no integration tests added.

1 files changed, 39 insertions, 0 deletions

diff --git a/web_src/svg/gitea-gitbucket.svg b/web_src/svg/gitea-gitbucket.svg
new file mode 100644
index 0000000000..24da154968
--- /dev/null
+++ b/web_src/svg/gitea-gitbucket.svg
@@ -0,0 +1,39 @@
+<?xml version="1.0" standalone="no"?>
+<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 20010904//EN"
+ "http://www.w3.org/TR/2001/REC-SVG-20010904/DTD/svg10.dtd">
+<svg version="1.0" xmlns="http://www.w3.org/2000/svg"
+ width="316.000000pt" height="329.000000pt" viewBox="0 0 316.000000 329.000000"
+ preserveAspectRatio="xMidYMid meet">
+<metadata>
+Created by potrace 1.14, written by Peter Selinger 2001-2017
+</metadata>
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+</svg>
\ No newline at end of file