Auto merge of #27069 - servo:dependabot/cargo/gstreamer-0.15.7, r=jdm

build(deps): bump gstreamer from 0.15.6 to 0.15.7

Bumps gstreamer from 0.15.6 to 0.15.7.

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Cargo.lock

@@ -2037,9 +2037,9 @@ dependencies = [
 
 [[package]]
 name = "gstreamer"
-version = "0.15.6"
+version = "0.15.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "eeec6021aec963d6c547cf3e4e6d4f24a8e128b1a54dc509a700c821f835c73a"
+checksum = "ce8664a114cd6ec16bece783d5eee59496919915b1f6884400ba4a953274a163"
 dependencies = [
  "bitflags",
  "cfg-if",