Update README.md (vdaas#2724)

Signed-off-by: Yusuke Kato <[email protected]>
Co-authored-by: Kiichiro YUKAWA <[email protected]>

README.md

@@ -10,7 +10,6 @@
 [![Go Reference](https://pkg.go.dev/badge/github.com/vdaas/vald.svg)](https://pkg.go.dev/github.com/vdaas/vald)
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 [![Go Report Card](https://goreportcard.com/badge/github.com/vdaas/vald?style=flat-square)](https://goreportcard.com/report/github.com/vdaas/vald)
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