Fix notbefore (#1384)

The CSV file and this page mention(ed) that the date in the CSV file is
the notBefore date of a certificate. However, it is the notAfter
datetime.

This is [already fixed in the
CSV](https://community.letsencrypt.org/t/questions-about-renewing-before-tls-alpn-01-revocations/170449/169),
but as [mentioned on the
Community](https://community.letsencrypt.org/t/is-the-date-in-the-third-column-notbefore-or-notafter/170912)
this page is still mentioning the date as notBefore (but in other
words).

This PR corrects the above.

This PR *also* changes back the `date` variable of the page to the date
the page was originally written, which was simultaneously updated with
the `lastmod` date in #1383 which *probably* shouldn't have. Correct me
if I'm wrong, but my gut says the `date` value is the date on which the
page was originally written and the `lastmod` value is the one which
needs to be updated with every update. And not `date`.

content/en/tlsalpnrevocation.md

@@ -2,8 +2,8 @@
 title: Download affected certificate serials for 2022.01.25 TLS-ALPN-01 Incident
 slug: tlsalpnrevocation
 top_graphic: 4
-date: 2022-01-27
-lastmod: 2022-04-26
+date: 2022-01-26
+lastmod: 2022-08-02
 english_is_canonical: 1
 show_lastmod: 1
 ---
@@ -35,9 +35,9 @@ Alternatively, the data set is available for download and local searching.
 The file tls-alpn-01-incident-affected-certs-by-regID.csv.gz was a gzipped CSV containing rows in the following format, but is no longer available.
 
 ```csv
-123456,"03e1ce2c0324f9ca93417fc8886f87f34857","2022-01-25T18:25:29Z","letsencrypt.org","www.letsencrypt.org","status.letsencrypt.org"
+123456,"03e1ce2c0324f9ca93417fc8886f87f34857","2022-02-25T18:25:29Z","letsencrypt.org","www.letsencrypt.org","status.letsencrypt.org"
 ```
 
-The first column is the [ID number](https://letsencrypt.org/docs/account-id/) of the account which requested issuance of the certificate. The file is sorted by account ID, so all certs issued by a single account are grouped together. The second column is the unique hexadecimal serial number of the certificate. The third column is the time at which the certificate was issued (in RFC3339 format, i.e. YYYY-MM-DDTHH:MM:SSZ, all times UTC). The remaining columns are all identifiers (DNS hostnames) that the certificate was issued for.
+The first column is the [ID number](https://letsencrypt.org/docs/account-id/) of the account which requested issuance of the certificate. The file is sorted by account ID, so all certs issued by a single account are grouped together. The second column is the unique hexadecimal serial number of the certificate. The third column is the expiration time of the certificate (in RFC3339 format, i.e. YYYY-MM-DDTHH:MM:SSZ, all times UTC). The remaining columns are all identifiers (DNS hostnames) that the certificate was issued for.
 
 You can download this file, unzip it with `gunzip` or the equivalent utility on your computer, and look up your account id(s). You need to renew and replace each certificate listed, unless you have already done so more recently than Jan 26, 2022, 00:48 UTC.