firefox_esr: Update version from 45.7.0 to 45.8.0

Release notes [1]:

> Version 45.8.0, first offered to ESR channel users on March 7, 2017
>
> Various security fixes [2]

Fixes for MFSA 2017-06 [3], also known as:

CVE-2017-5400, CVE-2017-5401, CVE-2017-5402, CVE-2017-5404,
CVE-2017-5407, CVE-2017-5410, CVE-2017-5408, CVE-2017-5405,
CVE-2017-5398.

[1] https://www.mozilla.org/en-US/firefox/45.8.0/releasenotes/
[2] https://www.mozilla.org/en-US/security/known-vulnerabilities/firefox-esr/#firefoxesr45.8
[3] https://www.mozilla.org/en-US/security/advisories/mfsa2017-06/

firefox_esr.be0

@@ -1,6 +1,6 @@
 #!/bin/env beesh
 
-# BEE_VERSION firefox_esr-45.7.0-0
+# BEE_VERSION firefox_esr-45.8.0-0
 
 #export BEE_TMP_TMPDIR=/dev/shm BEE_TMP_BUILDROOT=/dev/shm/bee-root BEE_MAKEFLAGS='-j80'