[beta] Prepare the 1.19.0 beta release

[alexcrichton]

• Update the cargo submodule
• Update the stage0 bootstrap to 1.18.0 release
• Update release channel to beta
• Disable the RLS (this'll happen next beta hopefully)

Closes#42357

[rust-highfive]

r? @nikomatsakis

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[alexcrichton]

@bors: r+ p=10

(this is the beta release)

[bors]

📌 Commit b63c47a has been approved by alexcrichton

[alexcrichton]

@bors: r+

[bors]

📌 Commit 15ab000 has been approved by alexcrichton

[bors]

⌛ Testing commit 15ab000 with merge e2d3d32...

[bors]

💔 Test failed - status-travis

[arielb1]

Looks like there is some incompatibility:

[00:56:54] error[E0308]: mismatched types
[00:56:54] --> /checkout/src/tools/rls/src/build.rs:334:32
[00:56:54] |
[00:56:54] 334 | return cmd.exec();
[00:56:54] | ^^^^^^^^^^ expected struct `cargo::util::ProcessError`, found struct `cargo::CargoError`
[00:56:54] |
[00:56:54] = note: expected type `std::result::Result<_, cargo::util::ProcessError>`
[00:56:54] found type `std::result::Result<_, cargo::CargoError>`

[alexcrichton]

@bors: r+

Looks like no submodule update for us

[bors]

📌 Commit 63a9089 has been approved by alexcrichton

[bors]

⌛ Testing commit 63a9089 with merge 1c46adf...

[bors]

💔 Test failed - status-travis

[alexcrichton]

@bors: r+

[bors]

📌 Commit 1dbacb3 has been approved by alexcrichton

[manfredbrandl]

@alexcrichton travis seems not to recognice that the job 53769.33 has finished compiling.

[bors]

⌛ Testing commit 1dbacb3 with merge 7350367...

[bors]

💔 Test failed - status-travis

[alexcrichton]

@bors: retry

• osx timed out :(

[bors]

⌛ Testing commit 1dbacb3 with merge a879841...

[bors]

☀️ Test successful - status-appveyor, status-travis
Approved by: alexcrichton
Pushing a879841 to beta...