build: Bump gin-gonic/gin from v1.4.0 to v1.7.7

[MaggotMouth]

Fixes #411

Security advisory published for gopkg.in/yaml.v2 prior to v2.2.8

Test runs:

$ go test
[Sentry] 2022/02/16 13:46:57 Using release from Git: v0.12.0-3-g8c12a8d
[Sentry] 2022/02/16 13:46:57 Sentry client initialized with an empty DSN. Using noopTransport. No events will be delivered.
[Sentry] 2022/02/16 13:46:57 Integration installed: ContextifyFrames
[Sentry] 2022/02/16 13:46:57 Integration installed: Environment
[Sentry] 2022/02/16 13:46:57 Integration installed: Modules
[Sentry] 2022/02/16 13:46:57 Integration installed: IgnoreErrors
[Sentry] 2022/02/16 13:46:57 The Modules integration is not available in binaries built without module support.
[Sentry] 2022/02/16 13:46:57 Event dropped due to noopTransport usage.
PASS
ok  	github.com/getsentry/sentry-go	1.189s

$ go test -race
[Sentry] 2022/02/16 13:47:02 Using release from Git: v0.12.0-3-g8c12a8d
[Sentry] 2022/02/16 13:47:02 Sentry client initialized with an empty DSN. Using noopTransport. No events will be delivered.
[Sentry] 2022/02/16 13:47:02 Integration installed: ContextifyFrames
[Sentry] 2022/02/16 13:47:02 Integration installed: Environment
[Sentry] 2022/02/16 13:47:02 Integration installed: Modules
[Sentry] 2022/02/16 13:47:02 Integration installed: IgnoreErrors
[Sentry] 2022/02/16 13:47:02 The Modules integration is not available in binaries built without module support.
[Sentry] 2022/02/16 13:47:02 Event dropped due to noopTransport usage.
PASS
ok  	github.com/getsentry/sentry-go	1.795s

[kamilogorek]

Thanks!