Update buildctl.md

Signed-off-by: yardstrong <yardstrong@163.com>

Author: YardStrong

cmd/buildctl/build.go

@@ -109,7 +109,7 @@ var buildCommand = cli.Command{
 		},
 		cli.StringSliceFlag{
 			Name:  "registry-auth-tlscontext",
-			Usage: "Overwrite TLS configuration when authenticating with registries, e.g. --registry-auth-tlscontext host=https://myserver:2376,insecure=false,ca=/path/to/my/ca.crt,cert=/path/to/my/cert.crt,key=/path/to/my/key.crt",
+			Usage: "Overwrite TLS configuration when authenticating with registries, e.g. --registry-auth-tlscontext host=myserver:2376,insecure=false,ca=/path/to/my/ca.crt,cert=/path/to/my/cert.crt,key=/path/to/my/key.crt",
 		},
 		cli.StringFlag{
 			Name:  "debug-json-cache-metrics",

docs/reference/buildctl.md

@@ -78,7 +78,7 @@ OPTIONS:
    --metadata-file value             Output build metadata (e.g., image digest) to a file as JSON
    --source-policy-file value        Read source policy file from a JSON file
    --ref-file value                  Write build ref to a file
-   --registry-auth-tlscontext value  Overwrite TLS configuration when authenticating with registries, e.g. --registry-auth-tlscontext host=https://myserver:2376,insecure=false,ca=/path/to/my/ca.crt,cert=/path/to/my/cert.crt,key=/path/to/my/key.crt
+   --registry-auth-tlscontext value  Overwrite TLS configuration when authenticating with registries, e.g. --registry-auth-tlscontext host=myserver:2376,insecure=false,ca=/path/to/my/ca.crt,cert=/path/to/my/cert.crt,key=/path/to/my/key.crt
    --debug-json-cache-metrics value  Where to output json cache metrics, use 'stdout' or 'stderr' for standard (error) output.
    
 ```