submodules: update clippy from 9897442 to 8c0e038

Changes:
````
Rustup for rust-lang#59042
Update pulldown_cmark to 0.5
Only run AppVeyor on r+, try and the master branch
Remove approx_constant known problems
Suppress let_and_return if let has attributes
Add test for or_fun_call macro suggestion
UI test cleanup: Extract needless_range_loop tests
Change "if types change" to "if you later change the type"
````

Cargo.lock

@@ -407,7 +407,7 @@ dependencies = [
  "itertools 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "matches 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)",
- "pulldown-cmark 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "pulldown-cmark 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "quine-mc_cluskey 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "regex-syntax 0.6.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "semver 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -2003,19 +2003,21 @@ dependencies = [
 
 [[package]]
 name = "pulldown-cmark"
-version = "0.2.0"
+version = "0.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "bitflags 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
- "getopts 0.2.17 (registry+https://github.com/rust-lang/crates.io-index)",
+ "memchr 2.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "unicase 2.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "pulldown-cmark"
-version = "0.4.1"
+version = "0.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "bitflags 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
+ "getopts 0.2.17 (registry+https://github.com/rust-lang/crates.io-index)",
  "memchr 2.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "unicase 2.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -4216,8 +4218,8 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum proc-macro2 0.4.24 (registry+https://github.com/rust-lang/crates.io-index)" = "77619697826f31a02ae974457af0b29b723e5619e113e9397b8b82c6bd253f09"
 "checksum proptest 0.9.2 (registry+https://github.com/rust-lang/crates.io-index)" = "24f5844db2f839e97e3021980975f6ebf8691d9b9b2ca67ed3feb38dc3edb52c"
 "checksum pulldown-cmark 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "d6fdf85cda6cadfae5428a54661d431330b312bc767ddbc57adbedc24da66e32"
-"checksum pulldown-cmark 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "eef52fac62d0ea7b9b4dc7da092aa64ea7ec3d90af6679422d3d7e0e14b6ee15"
 "checksum pulldown-cmark 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)" = "d1b74cc784b038a9921fd1a48310cc2e238101aa8ae0b94201e2d85121dd68b5"
+"checksum pulldown-cmark 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)" = "157737d41407de9c5e0563a991d085117d60ae729af2cc1bf28d6dfbc97bcc1f"
 "checksum quick-error 1.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "9274b940887ce9addde99c4eee6b5c44cc494b182b97e73dc8ffdcb3397fd3f0"
 "checksum quine-mc_cluskey 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)" = "07589615d719a60c8dd8a4622e7946465dfef20d1a428f969e3443e7386d5f45"
 "checksum quote 0.3.15 (registry+https://github.com/rust-lang/crates.io-index)" = "7a6e920b65c65f10b2ae65c831a81a073a89edd28c7cce89475bff467ab4167a"